It's a trap! I read it as a desperate attempt by manufacturers of memory modules to cause an artifical increase in demand, thus recovering DRAM prices. Sorry for top-posting. Petr T On Sat, 1 Apr 2023 11:46:58 +0200 Vlastimil Babka <vbabka@xxxxxxx> wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@xxxxxxxxx> > -M: Pekka Enberg <penberg@xxxxxxxxxx> > -M: David Rientjes <rientjes@xxxxxxxxxx> > -M: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > -M: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > -M: Vlastimil Babka <vbabka@xxxxxxx> > -R: Roman Gushchin <roman.gushchin@xxxxxxxxx> > -R: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx> > -L: linux-mm@xxxxxxxxx > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b* > - > SLCAN CAN NETWORK DRIVER > M: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> > L: linux-can@xxxxxxxxxxxxxxx > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 45af70315a94..61602d54b1d0 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -140,13 +140,14 @@ > > /* The following flags affect the page allocator grouping pages by mobility */ > /* Objects are reclaimable */ > -#ifndef CONFIG_SLUB_TINY > #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) > -#else > -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) > -#endif > #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ > > +#define KMALLOC_NOT_NORMAL_BITS \ > + (__GFP_RECLAIMABLE | \ > + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > + > /* > * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. > * > @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) > * Kmalloc array related definitions > */ > > -#ifdef CONFIG_SLAB > -/* > - * SLAB and SLUB directly allocates requests fitting in to an order-1 page > - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. > - */ > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 5 > -#endif > -#endif > - > -#ifdef CONFIG_SLUB > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 3 > -#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) > @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) > #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ > (KMALLOC_MIN_SIZE) : 16) > > -/* > - * Whenever changing this, take care of that kmalloc_type() and > - * create_kmalloc_caches() still work as intended. > - * > - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP > - * is for accounted but unreclaimable and non-dma objects. All the other > - * kmem caches can have both accounted and unaccounted objects. > - */ > -enum kmalloc_cache_type { > - KMALLOC_NORMAL = 0, > -#ifndef CONFIG_ZONE_DMA > - KMALLOC_DMA = KMALLOC_NORMAL, > -#endif > -#ifndef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP = KMALLOC_NORMAL, > -#endif > -#ifdef CONFIG_SLUB_TINY > - KMALLOC_RECLAIM = KMALLOC_NORMAL, > -#else > - KMALLOC_RECLAIM, > -#endif > -#ifdef CONFIG_ZONE_DMA > - KMALLOC_DMA, > -#endif > -#ifdef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP, > -#endif > - NR_KMALLOC_TYPES > -}; > - > -#ifndef CONFIG_SLOB > -extern struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; > - > -/* > - * Define gfp bits that should not be set for KMALLOC_NORMAL. > - */ > -#define KMALLOC_NOT_NORMAL_BITS \ > - (__GFP_RECLAIMABLE | \ > - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > - > -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > -{ > - /* > - * The most common case is KMALLOC_NORMAL, so test for it > - * with a single branch for all the relevant flags. > - */ > - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) > - return KMALLOC_NORMAL; > - > - /* > - * At least one of the flags has to be set. Their priorities in > - * decreasing order are: > - * 1) __GFP_DMA > - * 2) __GFP_RECLAIMABLE > - * 3) __GFP_ACCOUNT > - */ > - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) > - return KMALLOC_DMA; > - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) > - return KMALLOC_RECLAIM; > - else > - return KMALLOC_CGROUP; > -} > - > -/* > - * Figure out which kmalloc slab an allocation of a certain size > - * belongs to. > - * 0 = zero alloc > - * 1 = 65 .. 96 bytes > - * 2 = 129 .. 192 bytes > - * n = 2^(n-1)+1 .. 2^n > - * > - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; > - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. > - * Callers where !size_is_constant should only be test modules, where runtime > - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). > - */ > -static __always_inline unsigned int __kmalloc_index(size_t size, > - bool size_is_constant) > -{ > - if (!size) > - return 0; > - > - if (size <= KMALLOC_MIN_SIZE) > - return KMALLOC_SHIFT_LOW; > - > - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) > - return 1; > - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) > - return 2; > - if (size <= 8) return 3; > - if (size <= 16) return 4; > - if (size <= 32) return 5; > - if (size <= 64) return 6; > - if (size <= 128) return 7; > - if (size <= 256) return 8; > - if (size <= 512) return 9; > - if (size <= 1024) return 10; > - if (size <= 2 * 1024) return 11; > - if (size <= 4 * 1024) return 12; > - if (size <= 8 * 1024) return 13; > - if (size <= 16 * 1024) return 14; > - if (size <= 32 * 1024) return 15; > - if (size <= 64 * 1024) return 16; > - if (size <= 128 * 1024) return 17; > - if (size <= 256 * 1024) return 18; > - if (size <= 512 * 1024) return 19; > - if (size <= 1024 * 1024) return 20; > - if (size <= 2 * 1024 * 1024) return 21; > - > - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) > - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); > - else > - BUG(); > - > - /* Will never be reached. Needed because the compiler may complain */ > - return -1; > -} > -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); > > /** > @@ -567,57 +417,15 @@ 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) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - index = kmalloc_index(size); > - return kmalloc_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, size); > - } > - 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); > + return kmalloc_large(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) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - index = kmalloc_index(size); > - return kmalloc_node_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, node, size); > - } > - return __kmalloc_node(size, flags, node); > + return kmalloc_large_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. > @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); > > void __init kmem_cache_init_late(void); > > -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) > -int slab_prepare_cpu(unsigned int cpu); > -int slab_dead_cpu(unsigned int cpu); > -#else > #define slab_prepare_cpu NULL > #define slab_dead_cpu NULL > -#endif > > #endif /* _LINUX_SLAB_H */ > 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 */ > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > deleted file mode 100644 > index f6df03f934e5..000000000000 > --- a/include/linux/slub_def.h > +++ /dev/null > @@ -1,198 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLUB_DEF_H > -#define _LINUX_SLUB_DEF_H > - > -/* > - * SLUB : A Slab allocator without object queues. > - * > - * (C) 2007 SGI, Christoph Lameter > - */ > -#include <linux/kfence.h> > -#include <linux/kobject.h> > -#include <linux/reciprocal_div.h> > -#include <linux/local_lock.h> > - > -enum stat_item { > - ALLOC_FASTPATH, /* Allocation from cpu slab */ > - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ > - FREE_FASTPATH, /* Free to cpu slab */ > - FREE_SLOWPATH, /* Freeing not to cpu slab */ > - FREE_FROZEN, /* Freeing to frozen slab */ > - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ > - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ > - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ > - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ > - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ > - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ > - FREE_SLAB, /* Slab freed to the page allocator */ > - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ > - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ > - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ > - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ > - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ > - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ > - DEACTIVATE_BYPASS, /* Implicit deactivation */ > - ORDER_FALLBACK, /* Number of times fallback was necessary */ > - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ > - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ > - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ > - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ > - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ > - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ > - NR_SLUB_STAT_ITEMS }; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * When changing the layout, make sure freelist and tid are still compatible > - * with this_cpu_cmpxchg_double() alignment requirements. > - */ > -struct kmem_cache_cpu { > - void **freelist; /* Pointer to next available object */ > - unsigned long tid; /* Globally unique transaction id */ > - struct slab *slab; /* The slab from which we are allocating */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct slab *partial; /* Partially allocated frozen slabs */ > -#endif > - local_lock_t lock; /* Protects the fields above */ > -#ifdef CONFIG_SLUB_STATS > - unsigned stat[NR_SLUB_STAT_ITEMS]; > -#endif > -}; > -#endif /* CONFIG_SLUB_TINY */ > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -#define slub_percpu_partial(c) ((c)->partial) > - > -#define slub_set_percpu_partial(c, p) \ > -({ \ > - slub_percpu_partial(c) = (p)->next; \ > -}) > - > -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) > -#else > -#define slub_percpu_partial(c) NULL > - > -#define slub_set_percpu_partial(c, p) > - > -#define slub_percpu_partial_read_once(c) NULL > -#endif // CONFIG_SLUB_CPU_PARTIAL > - > -/* > - * Word size structure that can be atomically updated or read and that > - * contains both the order and the number of objects that a slab of the > - * given order would contain. > - */ > -struct kmem_cache_order_objects { > - unsigned int x; > -}; > - > -/* > - * Slab cache management. > - */ > -struct kmem_cache { > -#ifndef CONFIG_SLUB_TINY > - struct kmem_cache_cpu __percpu *cpu_slab; > -#endif > - /* Used for retrieving partial slabs, etc. */ > - slab_flags_t flags; > - unsigned long min_partial; > - unsigned int size; /* The size of an object including metadata */ > - unsigned int object_size;/* The size of an object without metadata */ > - struct reciprocal_value reciprocal_size; > - unsigned int offset; /* Free pointer offset */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - /* Number of per cpu partial objects to keep around */ > - unsigned int cpu_partial; > - /* Number of per cpu partial slabs to keep around */ > - unsigned int cpu_partial_slabs; > -#endif > - struct kmem_cache_order_objects oo; > - > - /* Allocation and freeing of slabs */ > - struct kmem_cache_order_objects min; > - gfp_t allocflags; /* gfp flags to use on each alloc */ > - int refcount; /* Refcount for slab cache destroy */ > - void (*ctor)(void *); > - unsigned int inuse; /* Offset to metadata */ > - unsigned int align; /* Alignment */ > - unsigned int red_left_pad; /* Left redzone padding size */ > - const char *name; /* Name (only for display!) */ > - struct list_head list; /* List of slab caches */ > -#ifdef CONFIG_SYSFS > - struct kobject kobj; /* For sysfs */ > -#endif > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - unsigned long random; > -#endif > - > -#ifdef CONFIG_NUMA > - /* > - * Defragmentation by allocating from a remote node. > - */ > - unsigned int remote_node_defrag_ratio; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#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]; > -}; > - > -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) > -#define SLAB_SUPPORTS_SYSFS > -void sysfs_slab_unlink(struct kmem_cache *); > -void sysfs_slab_release(struct kmem_cache *); > -#else > -static inline void sysfs_slab_unlink(struct kmem_cache *s) > -{ > -} > -static inline void sysfs_slab_release(struct kmem_cache *s) > -{ > -} > -#endif > - > -void *fixup_red_left(struct kmem_cache *s, void *p); > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) { > - void *object = x - (x - slab_address(slab)) % cache->size; > - void *last_object = slab_address(slab) + > - (slab->objects - 1) * cache->size; > - void *result = (unlikely(object > last_object)) ? last_object : object; > - > - result = fixup_red_left(cache, result); > - return result; > -} > - > -/* Determine object index from a given position */ > -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, > - void *addr, void *obj) > -{ > - return reciprocal_divide(kasan_reset_tag(obj) - addr, > - cache->reciprocal_size); > -} > - > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - if (is_kfence_address(obj)) > - return 0; > - return __obj_to_index(cache, slab_address(slab), obj); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - return slab->objects; > -} > -#endif /* _LINUX_SLUB_DEF_H */ > diff --git a/init/Kconfig b/init/Kconfig > index 1fb5f313d18f..45be2eedf75c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -973,7 +973,7 @@ config MEMCG > > config MEMCG_KMEM > bool > - depends on MEMCG && !SLOB > + depends on MEMCG && BROKEN > default y > > config BLK_CGROUP > diff --git a/mm/Kconfig b/mm/Kconfig > index 4751031f3f05..f07e81bca39e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE > > For more information, see zsmalloc documentation. > > -menu "SLAB allocator options" > - > -choice > - prompt "Choose SLAB allocator" > - default SLUB > - help > - This option allows to select a slab allocator. > - > -config SLAB > - bool "SLAB" > - depends on !PREEMPT_RT > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - The regular slab allocator that is established and known to work > - well in all environments. It organizes cache hot objects in > - per cpu and per node queues. > - > -config SLUB > - bool "SLUB (Unqueued Allocator)" > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - SLUB is a slab allocator that minimizes cache line usage > - instead of managing queues of cached objects (SLAB approach). > - Per cpu caching is realized using slabs of objects instead > - of queues of objects. SLUB can use memory efficiently > - and has enhanced diagnostics. SLUB is the default choice for > - a slab allocator. > - > -config SLOB_DEPRECATED > - depends on EXPERT > - bool "SLOB (Simple Allocator - DEPRECATED)" > - depends on !PREEMPT_RT > - help > - Deprecated and scheduled for removal in a few cycles. SLUB > - recommended as replacement. CONFIG_SLUB_TINY can be considered > - on systems with 16MB or less RAM. > - > - If you need SLOB to stay, please contact linux-mm@xxxxxxxxx and > - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, > - with your use case. > - > - SLOB replaces the stock allocator with a drastically simpler > - allocator. SLOB is generally more space efficient but > - does not perform as well on large systems. > - > -endchoice > - > -config SLOB > - bool > - default y > - depends on SLOB_DEPRECATED > - > -config SLUB_TINY > - bool "Configure SLUB for minimal memory footprint" > - depends on SLUB && EXPERT > - select SLAB_MERGE_DEFAULT > - help > - Configures the SLUB allocator in a way to achieve minimal memory > - footprint, sacrificing scalability, debugging and other features. > - This is intended only for the smallest system that had used the > - SLOB allocator and is not recommended for systems with more than > - 16MB RAM. > - > - If unsure, say N. > - > -config SLAB_MERGE_DEFAULT > - bool "Allow slab caches to be merged" > - default y > - depends on SLAB || SLUB > - help > - For reduced kernel memory fragmentation, slab caches can be > - merged when they share the same size and other characteristics. > - This carries a risk of kernel heap overflows being able to > - overwrite objects from merged caches (and more easily control > - cache layout), which makes such heap attacks easier to exploit > - by attackers. By keeping caches unmerged, these kinds of exploits > - can usually only damage objects in the same cache. To disable > - merging at runtime, "slab_nomerge" can be passed on the kernel > - command line. > - > -config SLAB_FREELIST_RANDOM > - bool "Randomize slab freelist" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Randomizes the freelist order used on creating new pages. This > - security feature reduces the predictability of the kernel slab > - allocator against heap overflows. > - > -config SLAB_FREELIST_HARDENED > - bool "Harden slab freelist metadata" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Many kernel heap attacks try to target slab cache metadata and > - other infrastructure. This options makes minor performance > - sacrifices to harden the kernel slab allocator against common > - freelist exploit methods. Some slab implementations have more > - sanity-checking than others. This option is most effective with > - CONFIG_SLUB. > - > -config SLUB_STATS > - default n > - bool "Enable SLUB performance statistics" > - depends on SLUB && SYSFS && !SLUB_TINY > - help > - SLUB statistics are useful to debug SLUBs allocation behavior in > - order find ways to optimize the allocator. This should never be > - enabled for production use since keeping statistics slows down > - the allocator by a few percentage points. The slabinfo command > - supports the determination of the most active slabs to figure > - out which slabs are relevant to a particular load. > - Try running: slabinfo -DA > - > -config SLUB_CPU_PARTIAL > - default y > - depends on SLUB && SMP && !SLUB_TINY > - bool "SLUB per cpu partial cache" > - help > - Per cpu partial caches accelerate objects allocation and freeing > - that is local to a processor at the price of more indeterminism > - in the latency of the free. On overflow these caches will be cleared > - which requires the taking of locks that may cause latency spikes. > - Typically one would choose no for a realtime system. > - > -endmenu # SLAB allocator options > - > config SHUFFLE_PAGE_ALLOCATOR > bool "Page allocator randomization" > - default SLAB_FREELIST_RANDOM && ACPI_NUMA > + default ACPI_NUMA > help > Randomization of the page allocator improves the average > utilization of a direct-mapped memory-side-cache. See section > @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR > 6.2a specification for an example of how a platform advertises > the presence of a memory-side-cache. There are also incidental > security benefits as it reduces the predictability of page > - allocations to compliment SLAB_FREELIST_RANDOM, but the > - default granularity of shuffling on the "MAX_ORDER - 1" i.e, > - 10th order of pages is selected based on cache utilization > - benefits on x86. > + allocations, but the default granularity of shuffling on the > + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on > + cache utilization benefits on x86. > > While the randomization improves cache utilization it may > negatively impact workloads on platforms without a cache. For > diff --git a/mm/Makefile b/mm/Makefile > index 8e105e5b3e29..18b0bb245fc3 100644 > --- a/mm/Makefile > +++ b/mm/Makefile > @@ -4,16 +4,12 @@ > # > > KASAN_SANITIZE_slab_common.o := n > -KASAN_SANITIZE_slab.o := n > -KASAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_kmemleak.o := n > > # These produce frequent data race reports: most of them are due to races on > # the same word but accesses to different bits of that word. Re-enable KCSAN > # for these when we have more consensus on what to do about them. > KCSAN_SANITIZE_slab_common.o := n > -KCSAN_SANITIZE_slab.o := n > -KCSAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_page_alloc.o := n > # But enable explicit instrumentation for memory barriers. > KCSAN_INSTRUMENT_BARRIERS := y > @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y > # flaky coverage that is not a function of syscall inputs. E.g. slab is out of > # free pages, or a task is migrated between nodes. > KCOV_INSTRUMENT_slab_common.o := n > -KCOV_INSTRUMENT_slob.o := n > -KCOV_INSTRUMENT_slab.o := n > -KCOV_INSTRUMENT_slub.o := n > KCOV_INSTRUMENT_page_alloc.o := n > KCOV_INSTRUMENT_debug-pagealloc.o := n > KCOV_INSTRUMENT_kmemleak.o := n > @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o > obj-$(CONFIG_NUMA) += mempolicy.o > obj-$(CONFIG_SPARSEMEM) += sparse.o > obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o > -obj-$(CONFIG_SLOB) += slob.o > obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o > obj-$(CONFIG_KSM) += ksm.o > obj-$(CONFIG_PAGE_POISONING) += page_poison.o > -obj-$(CONFIG_SLAB) += slab.o > -obj-$(CONFIG_SLUB) += slub.o > obj-$(CONFIG_KASAN) += kasan/ > obj-$(CONFIG_KFENCE) += kfence/ > obj-$(CONFIG_KMSAN) += kmsan/ > diff --git a/mm/slab.c b/mm/slab.c > deleted file mode 100644 > index edbe722fb906..000000000000 > --- a/mm/slab.c > +++ /dev/null > @@ -1,4046 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * linux/mm/slab.c > - * Written by Mark Hemment, 1996/97. > - * (markhe@xxxxxxxxxxxxxxxxx) > - * > - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli > - * > - * Major cleanup, different bufctl logic, per-cpu arrays > - * (c) 2000 Manfred Spraul > - * > - * Cleanup, make the head arrays unconditional, preparation for NUMA > - * (c) 2002 Manfred Spraul > - * > - * An implementation of the Slab Allocator as described in outline in; > - * UNIX Internals: The New Frontiers by Uresh Vahalia > - * Pub: Prentice Hall ISBN 0-13-101908-2 > - * or with a little more detail in; > - * The Slab Allocator: An Object-Caching Kernel Memory Allocator > - * Jeff Bonwick (Sun Microsystems). > - * Presented at: USENIX Summer 1994 Technical Conference > - * > - * The memory is organized in caches, one cache for each object type. > - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) > - * Each cache consists out of many slabs (they are small (usually one > - * page long) and always contiguous), and each slab contains multiple > - * initialized objects. > - * > - * This means, that your constructor is used only for newly allocated > - * slabs and you must pass objects with the same initializations to > - * kmem_cache_free. > - * > - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, > - * normal). If you need a special memory type, then must create a new > - * cache for that memory type. > - * > - * In order to reduce fragmentation, the slabs are sorted in 3 groups: > - * full slabs with 0 free objects > - * partial slabs > - * empty slabs with no allocated objects > - * > - * If partial slabs exist, then new allocations come from these slabs, > - * otherwise from empty slabs or new slabs are allocated. > - * > - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache > - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. > - * > - * Each cache has a short per-cpu head array, most allocs > - * and frees go into that array, and if that array overflows, then 1/2 > - * of the entries in the array are given back into the global cache. > - * The head array is strictly LIFO and should improve the cache hit rates. > - * On SMP, it additionally reduces the spinlock operations. > - * > - * The c_cpuarray may not be read with enabled local interrupts - > - * it's changed with a smp_call_function(). > - * > - * SMP synchronization: > - * constructors and destructors are called without any locking. > - * Several members in struct kmem_cache and struct slab never change, they > - * are accessed without any locking. > - * The per-cpu arrays are never accessed from the wrong cpu, no locking, > - * and local interrupts are disabled so slab code is preempt-safe. > - * The non-constant members are protected with a per-cache irq spinlock. > - * > - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch > - * in 2000 - many ideas in the current implementation are derived from > - * his patch. > - * > - * Further notes from the original documentation: > - * > - * 11 April '97. Started multi-threading - markhe > - * The global cache-chain is protected by the mutex 'slab_mutex'. > - * The sem is only needed when accessing/extending the cache-chain, which > - * can never happen inside an interrupt (kmem_cache_create(), > - * kmem_cache_shrink() and kmem_cache_reap()). > - * > - * At present, each engine can be growing a cache. This should be blocked. > - * > - * 15 March 2005. NUMA slab allocator. > - * Shai Fultheim <shai@xxxxxxxxxxxx>. > - * Shobhit Dayal <shobhit@xxxxxxxxxxxxxx> > - * Alok N Kataria <alokk@xxxxxxxxxxxxxx> > - * Christoph Lameter <christoph@xxxxxxxxxxx> > - * > - * Modified the slab allocator to be node aware on NUMA systems. > - * Each node has its own list of partial, free and full slabs. > - * All object allocations for a node occur from node specific slab lists. > - */ > - > -#include <linux/slab.h> > -#include <linux/mm.h> > -#include <linux/poison.h> > -#include <linux/swap.h> > -#include <linux/cache.h> > -#include <linux/interrupt.h> > -#include <linux/init.h> > -#include <linux/compiler.h> > -#include <linux/cpuset.h> > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/notifier.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/cpu.h> > -#include <linux/sysctl.h> > -#include <linux/module.h> > -#include <linux/rcupdate.h> > -#include <linux/string.h> > -#include <linux/uaccess.h> > -#include <linux/nodemask.h> > -#include <linux/kmemleak.h> > -#include <linux/mempolicy.h> > -#include <linux/mutex.h> > -#include <linux/fault-inject.h> > -#include <linux/rtmutex.h> > -#include <linux/reciprocal_div.h> > -#include <linux/debugobjects.h> > -#include <linux/memory.h> > -#include <linux/prefetch.h> > -#include <linux/sched/task_stack.h> > - > -#include <net/sock.h> > - > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > -#include <asm/page.h> > - > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -#include "slab.h" > - > -/* > - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * STATS - 1 to collect stats for /proc/slabinfo. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) > - */ > - > -#ifdef CONFIG_DEBUG_SLAB > -#define DEBUG 1 > -#define STATS 1 > -#define FORCED_DEBUG 1 > -#else > -#define DEBUG 0 > -#define STATS 0 > -#define FORCED_DEBUG 0 > -#endif > - > -/* Shouldn't this be in a header file somewhere? */ > -#define BYTES_PER_WORD sizeof(void *) > -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) > - > -#ifndef ARCH_KMALLOC_FLAGS > -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN > -#endif > - > -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ > - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) > - > -#if FREELIST_BYTE_INDEX > -typedef unsigned char freelist_idx_t; > -#else > -typedef unsigned short freelist_idx_t; > -#endif > - > -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) > - > -/* > - * struct array_cache > - * > - * Purpose: > - * - LIFO ordering, to hand out cache-warm objects from _alloc > - * - reduce the number of linked list operations > - * - reduce spinlock operations > - * > - * The limit is stored in the per-cpu structure to reduce the data cache > - * footprint. > - * > - */ > -struct array_cache { > - unsigned int avail; > - unsigned int limit; > - unsigned int batchcount; > - unsigned int touched; > - void *entry[]; /* > - * Must have this definition in here for the proper > - * alignment of array_cache. Also simplifies accessing > - * the entries. > - */ > -}; > - > -struct alien_cache { > - spinlock_t lock; > - struct array_cache ac; > -}; > - > -/* > - * Need this for bootstrapping a per node allocator. > - */ > -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) > -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; > -#define CACHE_CACHE 0 > -#define SIZE_NODE (MAX_NUMNODES) > - > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree); > -static void free_block(struct kmem_cache *cachep, void **objpp, int len, > - int node, struct list_head *list); > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); > -static void cache_reap(struct work_struct *unused); > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list); > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list); > - > -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) > - > -static void kmem_cache_node_init(struct kmem_cache_node *parent) > -{ > - INIT_LIST_HEAD(&parent->slabs_full); > - INIT_LIST_HEAD(&parent->slabs_partial); > - INIT_LIST_HEAD(&parent->slabs_free); > - parent->total_slabs = 0; > - parent->free_slabs = 0; > - parent->shared = NULL; > - parent->alien = NULL; > - parent->colour_next = 0; > - raw_spin_lock_init(&parent->list_lock); > - parent->free_objects = 0; > - parent->free_touched = 0; > -} > - > -#define MAKE_LIST(cachep, listp, slab, nodeid) \ > - do { \ > - INIT_LIST_HEAD(listp); \ > - list_splice(&get_node(cachep, nodeid)->slab, listp); \ > - } while (0) > - > -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ > - do { \ > - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ > - } while (0) > - > -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) > -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) > -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) > -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) > - > -#define BATCHREFILL_LIMIT 16 > -/* > - * Optimization question: fewer reaps means less probability for unnecessary > - * cpucache drain/refill cycles. > - * > - * OTOH the cpuarrays can contain lots of objects, > - * which could lock up otherwise freeable slabs. > - */ > -#define REAPTIMEOUT_AC (2*HZ) > -#define REAPTIMEOUT_NODE (4*HZ) > - > -#if STATS > -#define STATS_INC_ACTIVE(x) ((x)->num_active++) > -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) > -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) > -#define STATS_INC_GROWN(x) ((x)->grown++) > -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) > -#define STATS_SET_HIGH(x) \ > - do { \ > - if ((x)->num_active > (x)->high_mark) \ > - (x)->high_mark = (x)->num_active; \ > - } while (0) > -#define STATS_INC_ERR(x) ((x)->errors++) > -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) > -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) > -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) > -#define STATS_SET_FREEABLE(x, i) \ > - do { \ > - if ((x)->max_freeable < i) \ > - (x)->max_freeable = i; \ > - } while (0) > -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) > -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) > -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) > -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) > -#else > -#define STATS_INC_ACTIVE(x) do { } while (0) > -#define STATS_DEC_ACTIVE(x) do { } while (0) > -#define STATS_INC_ALLOCED(x) do { } while (0) > -#define STATS_INC_GROWN(x) do { } while (0) > -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) > -#define STATS_SET_HIGH(x) do { } while (0) > -#define STATS_INC_ERR(x) do { } while (0) > -#define STATS_INC_NODEALLOCS(x) do { } while (0) > -#define STATS_INC_NODEFREES(x) do { } while (0) > -#define STATS_INC_ACOVERFLOW(x) do { } while (0) > -#define STATS_SET_FREEABLE(x, i) do { } while (0) > -#define STATS_INC_ALLOCHIT(x) do { } while (0) > -#define STATS_INC_ALLOCMISS(x) do { } while (0) > -#define STATS_INC_FREEHIT(x) do { } while (0) > -#define STATS_INC_FREEMISS(x) do { } while (0) > -#endif > - > -#if DEBUG > - > -/* > - * memory layout of objects: > - * 0 : objp > - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that > - * the end of an object is aligned with the end of the real > - * allocation. Catches writes behind the end of the allocation. > - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: > - * redzone word. > - * cachep->obj_offset: The real object. > - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] > - * cachep->size - 1* BYTES_PER_WORD: last caller address > - * [BYTES_PER_WORD long] > - */ > -static int obj_offset(struct kmem_cache *cachep) > -{ > - return cachep->obj_offset; > -} > - > -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - return (unsigned long long *) (objp + obj_offset(cachep) - > - sizeof(unsigned long long)); > -} > - > -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - if (cachep->flags & SLAB_STORE_USER) > - return (unsigned long long *)(objp + cachep->size - > - sizeof(unsigned long long) - > - REDZONE_ALIGN); > - return (unsigned long long *) (objp + cachep->size - > - sizeof(unsigned long long)); > -} > - > -static void **dbg_userword(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); > - return (void **)(objp + cachep->size - BYTES_PER_WORD); > -} > - > -#else > - > -#define obj_offset(x) 0 > -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) > - > -#endif > - > -/* > - * Do not go above this order unless 0 objects fit into the slab or > - * overridden on the command line. > - */ > -#define SLAB_MAX_ORDER_HI 1 > -#define SLAB_MAX_ORDER_LO 0 > -static int slab_max_order = SLAB_MAX_ORDER_LO; > -static bool slab_max_order_set __initdata; > - > -static inline void *index_to_obj(struct kmem_cache *cache, > - const struct slab *slab, unsigned int idx) > -{ > - return slab->s_mem + cache->size * idx; > -} > - > -#define BOOT_CPUCACHE_ENTRIES 1 > -/* internal cache of cache description objs */ > -static struct kmem_cache kmem_cache_boot = { > - .batchcount = 1, > - .limit = BOOT_CPUCACHE_ENTRIES, > - .shared = 1, > - .size = sizeof(struct kmem_cache), > - .name = "kmem_cache", > -}; > - > -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); > - > -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) > -{ > - return this_cpu_ptr(cachep->cpu_cache); > -} > - > -/* > - * Calculate the number of objects and left-over bytes for a given buffer size. > - */ > -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, > - slab_flags_t flags, size_t *left_over) > -{ > - unsigned int num; > - size_t slab_size = PAGE_SIZE << gfporder; > - > - /* > - * The slab management structure can be either off the slab or > - * on it. For the latter case, the memory allocated for a > - * slab is used for: > - * > - * - @buffer_size bytes for each object > - * - One freelist_idx_t for each object > - * > - * We don't need to consider alignment of freelist because > - * freelist will be at the end of slab page. The objects will be > - * at the correct alignment. > - * > - * If the slab management structure is off the slab, then the > - * alignment will already be calculated into the size. Because > - * the slabs are all pages aligned, the objects will be at the > - * correct alignment when allocated. > - */ > - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { > - num = slab_size / buffer_size; > - *left_over = slab_size % buffer_size; > - } else { > - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); > - *left_over = slab_size % > - (buffer_size + sizeof(freelist_idx_t)); > - } > - > - return num; > -} > - > -#if DEBUG > -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) > - > -static void __slab_error(const char *function, struct kmem_cache *cachep, > - char *msg) > -{ > - pr_err("slab error in %s(): cache `%s': %s\n", > - function, cachep->name, msg); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > -#endif > - > -/* > - * By default on NUMA we use alien caches to stage the freeing of > - * objects allocated from other nodes. This causes massive memory > - * inefficiencies when using fake NUMA setup to split memory into a > - * large number of small nodes, so it can be disabled on the command > - * line > - */ > - > -static int use_alien_caches __read_mostly = 1; > -static int __init noaliencache_setup(char *s) > -{ > - use_alien_caches = 0; > - return 1; > -} > -__setup("noaliencache", noaliencache_setup); > - > -static int __init slab_max_order_setup(char *str) > -{ > - get_option(&str, &slab_max_order); > - slab_max_order = slab_max_order < 0 ? 0 : > - min(slab_max_order, MAX_ORDER - 1); > - slab_max_order_set = true; > - > - return 1; > -} > -__setup("slab_max_order=", slab_max_order_setup); > - > -#ifdef CONFIG_NUMA > -/* > - * Special reaping functions for NUMA systems called from cache_reap(). > - * These take care of doing round robin flushing of alien caches (containing > - * objects freed on different nodes from which they were allocated) and the > - * flushing of remote pcps by calling drain_node_pages. > - */ > -static DEFINE_PER_CPU(unsigned long, slab_reap_node); > - > -static void init_reap_node(int cpu) > -{ > - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), > - node_online_map); > -} > - > -static void next_reap_node(void) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - node = next_node_in(node, node_online_map); > - __this_cpu_write(slab_reap_node, node); > -} > - > -#else > -#define init_reap_node(cpu) do { } while (0) > -#define next_reap_node(void) do { } while (0) > -#endif > - > -/* > - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz > - * via the workqueue/eventd. > - * Add the CPU number into the expiration time to minimize the possibility of > - * the CPUs getting into lockstep and contending for the global cache chain > - * lock. > - */ > -static void start_cpu_timer(int cpu) > -{ > - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); > - > - if (reap_work->work.func == NULL) { > - init_reap_node(cpu); > - INIT_DEFERRABLE_WORK(reap_work, cache_reap); > - schedule_delayed_work_on(cpu, reap_work, > - __round_jiffies_relative(HZ, cpu)); > - } > -} > - > -static void init_arraycache(struct array_cache *ac, int limit, int batch) > -{ > - if (ac) { > - ac->avail = 0; > - ac->limit = limit; > - ac->batchcount = batch; > - ac->touched = 0; > - } > -} > - > -static struct array_cache *alloc_arraycache(int node, int entries, > - int batchcount, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); > - struct array_cache *ac = NULL; > - > - ac = kmalloc_node(memsize, gfp, node); > - /* > - * The array_cache structures contain pointers to free object. > - * However, when such objects are allocated or transferred to another > - * cache the pointers are not cleared and they could be counted as > - * valid references during a kmemleak scan. Therefore, kmemleak must > - * not scan such objects. > - */ > - kmemleak_no_scan(ac); > - init_arraycache(ac, entries, batchcount); > - return ac; > -} > - > -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - struct kmem_cache_node *n; > - int slab_node; > - LIST_HEAD(list); > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Transfer objects in one arraycache to another. > - * Locking must be handled by the caller. > - * > - * Return the number of entries transferred. > - */ > -static int transfer_objects(struct array_cache *to, > - struct array_cache *from, unsigned int max) > -{ > - /* Figure out how many entries to transfer */ > - int nr = min3(from->avail, max, to->limit - to->avail); > - > - if (!nr) > - return 0; > - > - memcpy(to->entry + to->avail, from->entry + from->avail - nr, > - sizeof(void *) *nr); > - > - from->avail -= nr; > - to->avail += nr; > - return nr; > -} > - > -/* &alien->lock must be held by alien callers. */ > -static __always_inline void __free_one(struct array_cache *ac, void *objp) > -{ > - /* Avoid trivial double-free. */ > - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) > - return; > - ac->entry[ac->avail++] = objp; > -} > - > -#ifndef CONFIG_NUMA > - > -#define drain_alien_cache(cachep, alien) do { } while (0) > -#define reap_alien(cachep, n) do { } while (0) > - > -static inline struct alien_cache **alloc_alien_cache(int node, > - int limit, gfp_t gfp) > -{ > - return NULL; > -} > - > -static inline void free_alien_cache(struct alien_cache **ac_ptr) > -{ > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - return 0; > -} > - > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return flags & ~__GFP_NOFAIL; > -} > - > -#else /* CONFIG_NUMA */ > - > -static struct alien_cache *__alloc_alien_cache(int node, int entries, > - int batch, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); > - struct alien_cache *alc = NULL; > - > - alc = kmalloc_node(memsize, gfp, node); > - if (alc) { > - kmemleak_no_scan(alc); > - init_arraycache(&alc->ac, entries, batch); > - spin_lock_init(&alc->lock); > - } > - return alc; > -} > - > -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) > -{ > - struct alien_cache **alc_ptr; > - int i; > - > - if (limit > 1) > - limit = 12; > - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); > - if (!alc_ptr) > - return NULL; > - > - for_each_node(i) { > - if (i == node || !node_online(i)) > - continue; > - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); > - if (!alc_ptr[i]) { > - for (i--; i >= 0; i--) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > - return NULL; > - } > - } > - return alc_ptr; > -} > - > -static void free_alien_cache(struct alien_cache **alc_ptr) > -{ > - int i; > - > - if (!alc_ptr) > - return; > - for_each_node(i) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > -} > - > -static void __drain_alien_cache(struct kmem_cache *cachep, > - struct array_cache *ac, int node, > - struct list_head *list) > -{ > - struct kmem_cache_node *n = get_node(cachep, node); > - > - if (ac->avail) { > - raw_spin_lock(&n->list_lock); > - /* > - * Stuff objects into the remote nodes shared array first. > - * That way we could avoid the overhead of putting the objects > - * into the free lists and getting them back later. > - */ > - if (n->shared) > - transfer_objects(n->shared, ac, ac->limit); > - > - free_block(cachep, ac->entry, ac->avail, node, list); > - ac->avail = 0; > - raw_spin_unlock(&n->list_lock); > - } > -} > - > -/* > - * Called from cache_reap() to regularly drain alien caches round robin. > - */ > -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - if (n->alien) { > - struct alien_cache *alc = n->alien[node]; > - struct array_cache *ac; > - > - if (alc) { > - ac = &alc->ac; > - if (ac->avail && spin_trylock_irq(&alc->lock)) { > - LIST_HEAD(list); > - > - __drain_alien_cache(cachep, ac, node, &list); > - spin_unlock_irq(&alc->lock); > - slabs_destroy(cachep, &list); > - } > - } > - } > -} > - > -static void drain_alien_cache(struct kmem_cache *cachep, > - struct alien_cache **alien) > -{ > - int i = 0; > - struct alien_cache *alc; > - struct array_cache *ac; > - unsigned long flags; > - > - for_each_online_node(i) { > - alc = alien[i]; > - if (alc) { > - LIST_HEAD(list); > - > - ac = &alc->ac; > - spin_lock_irqsave(&alc->lock, flags); > - __drain_alien_cache(cachep, ac, i, &list); > - spin_unlock_irqrestore(&alc->lock, flags); > - slabs_destroy(cachep, &list); > - } > - } > -} > - > -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, > - int node, int slab_node) > -{ > - struct kmem_cache_node *n; > - struct alien_cache *alien = NULL; > - struct array_cache *ac; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - STATS_INC_NODEFREES(cachep); > - if (n->alien && n->alien[slab_node]) { > - alien = n->alien[slab_node]; > - ac = &alien->ac; > - spin_lock(&alien->lock); > - if (unlikely(ac->avail == ac->limit)) { > - STATS_INC_ACOVERFLOW(cachep); > - __drain_alien_cache(cachep, ac, slab_node, &list); > - } > - __free_one(ac, objp); > - spin_unlock(&alien->lock); > - slabs_destroy(cachep, &list); > - } else { > - n = get_node(cachep, slab_node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - return 1; > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - int slab_node = slab_nid(virt_to_slab(objp)); > - int node = numa_mem_id(); > - /* > - * Make sure we are not freeing an object from another node to the array > - * cache on this cpu. > - */ > - if (likely(node == slab_node)) > - return 0; > - > - return __cache_free_alien(cachep, objp, node, slab_node); > -} > - > -/* > - * Construct gfp mask to allocate from a specific node but do not reclaim or > - * warn about failures. > - */ > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); > -} > -#endif > - > -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) > -{ > - struct kmem_cache_node *n; > - > - /* > - * Set up the kmem_cache_node for cpu before we can > - * begin anything. Make sure some other cpu on this > - * node has not already allocated this > - */ > - n = get_node(cachep, node); > - if (n) { > - raw_spin_lock_irq(&n->list_lock); > - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + > - cachep->num; > - raw_spin_unlock_irq(&n->list_lock); > - > - return 0; > - } > - > - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); > - if (!n) > - return -ENOMEM; > - > - kmem_cache_node_init(n); > - n->next_reap = jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - n->free_limit = > - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; > - > - /* > - * The kmem_cache_nodes don't come and go as CPUs > - * come and go. slab_mutex provides sufficient > - * protection here. > - */ > - cachep->node[node] = n; > - > - return 0; > -} > - > -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) > -/* > - * Allocates and initializes node for a node on each slab cache, used for > - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node > - * will be allocated off-node since memory is not yet online for the new node. > - * When hotplugging memory or a cpu, existing nodes are not replaced if > - * already in use. > - * > - * Must hold slab_mutex. > - */ > -static int init_cache_node_node(int node) > -{ > - int ret; > - struct kmem_cache *cachep; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - ret = init_cache_node(cachep, node, GFP_KERNEL); > - if (ret) > - return ret; > - } > - > - return 0; > -} > -#endif > - > -static int setup_kmem_cache_node(struct kmem_cache *cachep, > - int node, gfp_t gfp, bool force_change) > -{ > - int ret = -ENOMEM; > - struct kmem_cache_node *n; > - struct array_cache *old_shared = NULL; > - struct array_cache *new_shared = NULL; > - struct alien_cache **new_alien = NULL; > - LIST_HEAD(list); > - > - if (use_alien_caches) { > - new_alien = alloc_alien_cache(node, cachep->limit, gfp); > - if (!new_alien) > - goto fail; > - } > - > - if (cachep->shared) { > - new_shared = alloc_arraycache(node, > - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); > - if (!new_shared) > - goto fail; > - } > - > - ret = init_cache_node(cachep, node, gfp); > - if (ret) > - goto fail; > - > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - if (n->shared && force_change) { > - free_block(cachep, n->shared->entry, > - n->shared->avail, node, &list); > - n->shared->avail = 0; > - } > - > - if (!n->shared || force_change) { > - old_shared = n->shared; > - n->shared = new_shared; > - new_shared = NULL; > - } > - > - if (!n->alien) { > - n->alien = new_alien; > - new_alien = NULL; > - } > - > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - > - /* > - * To protect lockless access to n->shared during irq disabled context. > - * If n->shared isn't NULL in irq disabled context, accessing to it is > - * guaranteed to be valid until irq is re-enabled, because it will be > - * freed after synchronize_rcu(). > - */ > - if (old_shared && force_change) > - synchronize_rcu(); > - > -fail: > - kfree(old_shared); > - kfree(new_shared); > - free_alien_cache(new_alien); > - > - return ret; > -} > - > -#ifdef CONFIG_SMP > - > -static void cpuup_canceled(long cpu) > -{ > - struct kmem_cache *cachep; > - struct kmem_cache_node *n = NULL; > - int node = cpu_to_mem(cpu); > - const struct cpumask *mask = cpumask_of_node(node); > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct array_cache *nc; > - struct array_cache *shared; > - struct alien_cache **alien; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - raw_spin_lock_irq(&n->list_lock); > - > - /* Free limit for this kmem_cache_node */ > - n->free_limit -= cachep->batchcount; > - > - /* cpu is dead; no one can alloc from it. */ > - nc = per_cpu_ptr(cachep->cpu_cache, cpu); > - free_block(cachep, nc->entry, nc->avail, node, &list); > - nc->avail = 0; > - > - if (!cpumask_empty(mask)) { > - raw_spin_unlock_irq(&n->list_lock); > - goto free_slab; > - } > - > - shared = n->shared; > - if (shared) { > - free_block(cachep, shared->entry, > - shared->avail, node, &list); > - n->shared = NULL; > - } > - > - alien = n->alien; > - n->alien = NULL; > - > - raw_spin_unlock_irq(&n->list_lock); > - > - kfree(shared); > - if (alien) { > - drain_alien_cache(cachep, alien); > - free_alien_cache(alien); > - } > - > -free_slab: > - slabs_destroy(cachep, &list); > - } > - /* > - * In the previous loop, all the objects were freed to > - * the respective cache's slabs, now we can go ahead and > - * shrink each nodelist to its limit. > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - n = get_node(cachep, node); > - if (!n) > - continue; > - drain_freelist(cachep, n, INT_MAX); > - } > -} > - > -static int cpuup_prepare(long cpu) > -{ > - struct kmem_cache *cachep; > - int node = cpu_to_mem(cpu); > - int err; > - > - /* > - * We need to do this right in the beginning since > - * alloc_arraycache's are going to use this list. > - * kmalloc_node allows us to add the slab to the right > - * kmem_cache_node and not this cpu's kmem_cache_node > - */ > - err = init_cache_node_node(node); > - if (err < 0) > - goto bad; > - > - /* > - * Now we can go ahead with allocating the shared arrays and > - * array caches > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); > - if (err) > - goto bad; > - } > - > - return 0; > -bad: > - cpuup_canceled(cpu); > - return -ENOMEM; > -} > - > -int slab_prepare_cpu(unsigned int cpu) > -{ > - int err; > - > - mutex_lock(&slab_mutex); > - err = cpuup_prepare(cpu); > - mutex_unlock(&slab_mutex); > - return err; > -} > - > -/* > - * This is called for a failed online attempt and for a successful > - * offline. > - * > - * Even if all the cpus of a node are down, we don't free the > - * kmem_cache_node of any cache. This is to avoid a race between cpu_down, and > - * a kmalloc allocation from another cpu for memory from the node of > - * the cpu going down. The kmem_cache_node structure is usually allocated from > - * kmem_cache_create() and gets destroyed at kmem_cache_destroy(). > - */ > -int slab_dead_cpu(unsigned int cpu) > -{ > - mutex_lock(&slab_mutex); > - cpuup_canceled(cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > -#endif > - > -static int slab_online_cpu(unsigned int cpu) > -{ > - start_cpu_timer(cpu); > - return 0; > -} > - > -static int slab_offline_cpu(unsigned int cpu) > -{ > - /* > - * Shutdown cache reaper. Note that the slab_mutex is held so > - * that if cache_reap() is invoked it cannot do anything > - * expensive but will only modify reap_work and reschedule the > - * timer. > - */ > - cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu)); > - /* Now the cache_reaper is guaranteed to be not running. */ > - per_cpu(slab_reap_work, cpu).work.func = NULL; > - return 0; > -} > - > -#if defined(CONFIG_NUMA) > -/* > - * Drains freelist for a node on each slab cache, used for memory hot-remove. > - * Returns -EBUSY if all objects cannot be drained so that the node is not > - * removed. > - * > - * Must hold slab_mutex. > - */ > -static int __meminit drain_cache_node_node(int node) > -{ > - struct kmem_cache *cachep; > - int ret = 0; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct kmem_cache_node *n; > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - drain_freelist(cachep, n, INT_MAX); > - > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) { > - ret = -EBUSY; > - break; > - } > - } > - return ret; > -} > - > -static int __meminit slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - struct memory_notify *mnb = arg; > - int ret = 0; > - int nid; > - > - nid = mnb->status_change_nid; > - if (nid < 0) > - goto out; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - mutex_lock(&slab_mutex); > - ret = init_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_GOING_OFFLINE: > - mutex_lock(&slab_mutex); > - ret = drain_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_ONLINE: > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > -out: > - return notifier_from_errno(ret); > -} > -#endif /* CONFIG_NUMA */ > - > -/* > - * swap the static kmem_cache_node with kmalloced memory > - */ > -static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *list, > - int nodeid) > -{ > - struct kmem_cache_node *ptr; > - > - ptr = kmalloc_node(sizeof(struct kmem_cache_node), GFP_NOWAIT, nodeid); > - BUG_ON(!ptr); > - > - memcpy(ptr, list, sizeof(struct kmem_cache_node)); > - /* > - * Do not assume that spinlocks can be initialized via memcpy: > - */ > - raw_spin_lock_init(&ptr->list_lock); > - > - MAKE_ALL_LISTS(cachep, ptr, nodeid); > - cachep->node[nodeid] = ptr; > -} > - > -/* > - * For setting up all the kmem_cache_node for cache whose buffer_size is same as > - * size of kmem_cache_node. > - */ > -static void __init set_up_node(struct kmem_cache *cachep, int index) > -{ > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = &init_kmem_cache_node[index + node]; > - cachep->node[node]->next_reap = jiffies + > - REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - } > -} > - > -/* > - * Initialisation. Called after the page allocator have been initialised and > - * before smp_init(). > - */ > -void __init kmem_cache_init(void) > -{ > - int i; > - > - kmem_cache = &kmem_cache_boot; > - > - if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) > - use_alien_caches = 0; > - > - for (i = 0; i < NUM_INIT_LISTS; i++) > - kmem_cache_node_init(&init_kmem_cache_node[i]); > - > - /* > - * Fragmentation resistance on low memory - only use bigger > - * page orders on machines with more than 32MB of memory if > - * not overridden on the command line. > - */ > - if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT) > - slab_max_order = SLAB_MAX_ORDER_HI; > - > - /* Bootstrap is tricky, because several objects are allocated > - * from caches that do not exist yet: > - * 1) initialize the kmem_cache cache: it contains the struct > - * kmem_cache structures of all caches, except kmem_cache itself: > - * kmem_cache is statically allocated. > - * Initially an __init data area is used for the head array and the > - * kmem_cache_node structures, it's replaced with a kmalloc allocated > - * array at the end of the bootstrap. > - * 2) Create the first kmalloc cache. > - * The struct kmem_cache for the new cache is allocated normally. > - * An __init data area is used for the head array. > - * 3) Create the remaining kmalloc caches, with minimally sized > - * head arrays. > - * 4) Replace the __init data head arrays for kmem_cache and the first > - * kmalloc cache with kmalloc allocated arrays. > - * 5) Replace the __init data for kmem_cache_node for kmem_cache and > - * the other cache's with kmalloc allocated memory. > - * 6) Resize the head arrays of the kmalloc caches to their final sizes. > - */ > - > - /* 1) create the kmem_cache */ > - > - /* > - * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids > - */ > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - list_add(&kmem_cache->list, &slab_caches); > - slab_state = PARTIAL; > - > - /* > - * Initialize the caches that provide memory for the kmem_cache_node > - * structures first. Without this, further allocations will bug. > - */ > - kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache( > - kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL], > - kmalloc_info[INDEX_NODE].size, > - ARCH_KMALLOC_FLAGS, 0, > - kmalloc_info[INDEX_NODE].size); > - slab_state = PARTIAL_NODE; > - setup_kmalloc_cache_index_table(); > - > - /* 5) Replace the bootstrap kmem_cache_node */ > - { > - int nid; > - > - for_each_online_node(nid) { > - init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid); > - > - init_list(kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE], > - &init_kmem_cache_node[SIZE_NODE + nid], nid); > - } > - } > - > - create_kmalloc_caches(ARCH_KMALLOC_FLAGS); > -} > - > -void __init kmem_cache_init_late(void) > -{ > - struct kmem_cache *cachep; > - > - /* 6) resize the head arrays to their final sizes */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(cachep, &slab_caches, list) > - if (enable_cpucache(cachep, GFP_NOWAIT)) > - BUG(); > - mutex_unlock(&slab_mutex); > - > - /* Done! */ > - slab_state = FULL; > - > -#ifdef CONFIG_NUMA > - /* > - * Register a memory hotplug callback that initializes and frees > - * node. > - */ > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > -#endif > - > - /* > - * The reap timers are started later, with a module init call: That part > - * of the kernel is not yet operational. > - */ > -} > - > -static int __init cpucache_init(void) > -{ > - int ret; > - > - /* > - * Register the timers that return unneeded pages to the page allocator > - */ > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online", > - slab_online_cpu, slab_offline_cpu); > - WARN_ON(ret < 0); > - > - return 0; > -} > -__initcall(cpucache_init); > - > -static noinline void > -slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) > -{ > -#if DEBUG > - struct kmem_cache_node *n; > - unsigned long flags; > - int node; > - static DEFINE_RATELIMIT_STATE(slab_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs)) > - return; > - > - pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nodeid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %d, order: %d\n", > - cachep->name, cachep->size, cachep->gfporder); > - > - for_each_kmem_cache_node(cachep, node, n) { > - unsigned long total_slabs, free_slabs, free_objs; > - > - raw_spin_lock_irqsave(&n->list_lock, flags); > - total_slabs = n->total_slabs; > - free_slabs = n->free_slabs; > - free_objs = n->free_objects; > - raw_spin_unlock_irqrestore(&n->list_lock, flags); > - > - pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", > - node, total_slabs - free_slabs, total_slabs, > - (total_slabs * cachep->num) - free_objs, > - total_slabs * cachep->num); > - } > -#endif > -} > - > -/* > - * Interface to system's page allocator. No need to hold the > - * kmem_cache_node ->list_lock. > - * > - * If we requested dmaable memory, we will get it. Even if we > - * did not request dmaable memory, we might get it, but that > - * would be relatively rare and ignorable. > - */ > -static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct folio *folio; > - struct slab *slab; > - > - flags |= cachep->allocflags; > - > - folio = (struct folio *) __alloc_pages_node(nodeid, flags, cachep->gfporder); > - if (!folio) { > - slab_out_of_memory(cachep, flags, nodeid); > - return NULL; > - } > - > - slab = folio_slab(folio); > - > - account_slab(slab, cachep->gfporder, cachep, flags); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ > - if (sk_memalloc_socks() && folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -/* > - * Interface to system's page release. > - */ > -static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) > -{ > - int order = cachep->gfporder; > - struct folio *folio = slab_folio(slab); > - > - BUG_ON(!folio_test_slab(folio)); > - __slab_clear_pfmemalloc(slab); > - page_mapcount_reset(&folio->page); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - unaccount_slab(slab, order, cachep); > - __free_pages(&folio->page, order); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct kmem_cache *cachep; > - struct slab *slab; > - > - slab = container_of(head, struct slab, rcu_head); > - cachep = slab->slab_cache; > - > - kmem_freepages(cachep, slab); > -} > - > -#if DEBUG > -static inline bool is_debug_pagealloc_cache(struct kmem_cache *cachep) > -{ > - return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > - ((cachep->size % PAGE_SIZE) == 0); > -} > - > -#ifdef CONFIG_DEBUG_PAGEALLOC > -static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) > -{ > - if (!is_debug_pagealloc_cache(cachep)) > - return; > - > - __kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); > -} > - > -#else > -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, > - int map) {} > - > -#endif > - > -static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) > -{ > - int size = cachep->object_size; > - addr = &((char *)addr)[obj_offset(cachep)]; > - > - memset(addr, val, size); > - *(unsigned char *)(addr + size - 1) = POISON_END; > -} > - > -static void dump_line(char *data, int offset, int limit) > -{ > - int i; > - unsigned char error = 0; > - int bad_count = 0; > - > - pr_err("%03x: ", offset); > - for (i = 0; i < limit; i++) { > - if (data[offset + i] != POISON_FREE) { > - error = data[offset + i]; > - bad_count++; > - } > - } > - print_hex_dump(KERN_CONT, "", 0, 16, 1, > - &data[offset], limit, 1); > - > - if (bad_count == 1) { > - error ^= POISON_FREE; > - if (!(error & (error - 1))) { > - pr_err("Single bit error detected. Probably bad RAM.\n"); > -#ifdef CONFIG_X86 > - pr_err("Run memtest86+ or a similar memory test tool.\n"); > -#else > - pr_err("Run a memory test tool.\n"); > -#endif > - } > - } > -} > -#endif > - > -#if DEBUG > - > -static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) > -{ > - int i, size; > - char *realobj; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - pr_err("Redzone: 0x%llx/0x%llx\n", > - *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - > - if (cachep->flags & SLAB_STORE_USER) > - pr_err("Last user: (%pSR)\n", *dbg_userword(cachep, objp)); > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - for (i = 0; i < size && lines; i += 16, lines--) { > - int limit; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - } > -} > - > -static void check_poison_obj(struct kmem_cache *cachep, void *objp) > -{ > - char *realobj; > - int size, i; > - int lines = 0; > - > - if (is_debug_pagealloc_cache(cachep)) > - return; > - > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - > - for (i = 0; i < size; i++) { > - char exp = POISON_FREE; > - if (i == size - 1) > - exp = POISON_END; > - if (realobj[i] != exp) { > - int limit; > - /* Mismatch ! */ > - /* Print header */ > - if (lines == 0) { > - pr_err("Slab corruption (%s): %s start=%px, len=%d\n", > - print_tainted(), cachep->name, > - realobj, size); > - print_objinfo(cachep, objp, 0); > - } > - /* Hexdump the affected line */ > - i = (i / 16) * 16; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - i += 16; > - lines++; > - /* Limit to 5 lines */ > - if (lines > 5) > - break; > - } > - } > - if (lines != 0) { > - /* Print some data about the neighboring objects, if they > - * exist: > - */ > - struct slab *slab = virt_to_slab(objp); > - unsigned int objnr; > - > - objnr = obj_to_index(cachep, slab, objp); > - if (objnr) { > - objp = index_to_obj(cachep, slab, objnr - 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Prev obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - if (objnr + 1 < cachep->num) { > - objp = index_to_obj(cachep, slab, objnr + 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Next obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - } > -} > -#endif > - > -#if DEBUG > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - > - if (OBJFREELIST_SLAB(cachep) && cachep->flags & SLAB_POISON) { > - poison_obj(cachep, slab->freelist - obj_offset(cachep), > - POISON_FREE); > - } > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - } > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "start of a freed object was overwritten"); > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "end of a freed object was overwritten"); > - } > - } > -} > -#else > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > -} > -#endif > - > -/** > - * slab_destroy - destroy and release all objects in a slab > - * @cachep: cache pointer being destroyed > - * @slab: slab being destroyed > - * > - * Destroy all the objs in a slab, and release the mem back to the system. > - * Before calling the slab must have been unlinked from the cache. The > - * kmem_cache_node ->list_lock is not held/needed. > - */ > -static void slab_destroy(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *freelist; > - > - freelist = slab->freelist; > - slab_destroy_debugcheck(cachep, slab); > - if (unlikely(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, kmem_rcu_free); > - else > - kmem_freepages(cachep, slab); > - > - /* > - * From now on, we don't use freelist > - * although actual page can be freed in rcu context > - */ > - if (OFF_SLAB(cachep)) > - kfree(freelist); > -} > - > -/* > - * Update the size of the caches before calling slabs_destroy as it may > - * recursively call kfree. > - */ > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list) > -{ > - struct slab *slab, *n; > - > - list_for_each_entry_safe(slab, n, list, slab_list) { > - list_del(&slab->slab_list); > - slab_destroy(cachep, slab); > - } > -} > - > -/** > - * calculate_slab_order - calculate size (page order) of slabs > - * @cachep: pointer to the cache that is being created > - * @size: size of objects to be created in this cache. > - * @flags: slab allocation flags > - * > - * Also calculates the number of objects per slab. > - * > - * This could be made much more intelligent. For now, try to avoid using > - * high order pages for slabs. When the gfp() functions are more friendly > - * towards high-order requests, this should be changed. > - * > - * Return: number of left-over bytes in a slab > - */ > -static size_t calculate_slab_order(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left_over = 0; > - int gfporder; > - > - for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { > - unsigned int num; > - size_t remainder; > - > - num = cache_estimate(gfporder, size, flags, &remainder); > - if (!num) > - continue; > - > - /* Can't handle number of objects more than SLAB_OBJ_MAX_NUM */ > - if (num > SLAB_OBJ_MAX_NUM) > - break; > - > - if (flags & CFLGS_OFF_SLAB) { > - struct kmem_cache *freelist_cache; > - size_t freelist_size; > - size_t freelist_cache_size; > - > - freelist_size = num * sizeof(freelist_idx_t); > - if (freelist_size > KMALLOC_MAX_CACHE_SIZE) { > - freelist_cache_size = PAGE_SIZE << get_order(freelist_size); > - } else { > - freelist_cache = kmalloc_slab(freelist_size, 0u); > - if (!freelist_cache) > - continue; > - freelist_cache_size = freelist_cache->size; > - > - /* > - * Needed to avoid possible looping condition > - * in cache_grow_begin() > - */ > - if (OFF_SLAB(freelist_cache)) > - continue; > - } > - > - /* check if off slab has enough benefit */ > - if (freelist_cache_size > cachep->size / 2) > - continue; > - } > - > - /* Found something acceptable - save it away */ > - cachep->num = num; > - cachep->gfporder = gfporder; > - left_over = remainder; > - > - /* > - * A VFS-reclaimable slab tends to have most allocations > - * as GFP_NOFS and we really don't want to have to be allocating > - * higher-order pages when we are unable to shrink dcache. > - */ > - if (flags & SLAB_RECLAIM_ACCOUNT) > - break; > - > - /* > - * Large number of objects is good, but very large slabs are > - * currently bad for the gfp()s. > - */ > - if (gfporder >= slab_max_order) > - break; > - > - /* > - * Acceptable internal fragmentation? > - */ > - if (left_over * 8 <= (PAGE_SIZE << gfporder)) > - break; > - } > - return left_over; > -} > - > -static struct array_cache __percpu *alloc_kmem_cache_cpus( > - struct kmem_cache *cachep, int entries, int batchcount) > -{ > - int cpu; > - size_t size; > - struct array_cache __percpu *cpu_cache; > - > - size = sizeof(void *) * entries + sizeof(struct array_cache); > - cpu_cache = __alloc_percpu(size, sizeof(void *)); > - > - if (!cpu_cache) > - return NULL; > - > - for_each_possible_cpu(cpu) { > - init_arraycache(per_cpu_ptr(cpu_cache, cpu), > - entries, batchcount); > - } > - > - return cpu_cache; > -} > - > -static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - if (slab_state >= FULL) > - return enable_cpucache(cachep, gfp); > - > - cachep->cpu_cache = alloc_kmem_cache_cpus(cachep, 1, 1); > - if (!cachep->cpu_cache) > - return 1; > - > - if (slab_state == DOWN) { > - /* Creation of first cache (kmem_cache). */ > - set_up_node(kmem_cache, CACHE_CACHE); > - } else if (slab_state == PARTIAL) { > - /* For kmem_cache_node */ > - set_up_node(cachep, SIZE_NODE); > - } else { > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = kmalloc_node( > - sizeof(struct kmem_cache_node), gfp, node); > - BUG_ON(!cachep->node[node]); > - kmem_cache_node_init(cachep->node[node]); > - } > - } > - > - cachep->node[numa_mem_id()]->next_reap = > - jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - cpu_cache_get(cachep)->avail = 0; > - cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; > - cpu_cache_get(cachep)->batchcount = 1; > - cpu_cache_get(cachep)->touched = 0; > - cachep->batchcount = 1; > - cachep->limit = BOOT_CPUCACHE_ENTRIES; > - return 0; > -} > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *cachep; > - > - cachep = find_mergeable(size, align, flags, name, ctor); > - if (cachep) { > - cachep->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - cachep->object_size = max_t(int, cachep->object_size, size); > - } > - return cachep; > -} > - > -static bool set_objfreelist_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * If slab auto-initialization on free is enabled, store the freelist > - * off-slab, so that its contents don't end up in one of the allocated > - * objects. > - */ > - if (unlikely(slab_want_init_on_free(cachep))) > - return false; > - > - if (cachep->ctor || flags & SLAB_TYPESAFE_BY_RCU) > - return false; > - > - left = calculate_slab_order(cachep, size, > - flags | CFLGS_OBJFREELIST_SLAB); > - if (!cachep->num) > - return false; > - > - if (cachep->num * sizeof(freelist_idx_t) > cachep->object_size) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_off_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * Always use on-slab management when SLAB_NOLEAKTRACE > - * to avoid recursive calls into kmemleak. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - return false; > - > - /* > - * Size is large, assume best to place the slab management obj > - * off-slab (should allow better packing of objs). > - */ > - left = calculate_slab_order(cachep, size, flags | CFLGS_OFF_SLAB); > - if (!cachep->num) > - return false; > - > - /* > - * If the slab has been placed off-slab, and we have enough space then > - * move it on-slab. This is at the expense of any extra colouring. > - */ > - if (left >= cachep->num * sizeof(freelist_idx_t)) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_on_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - left = calculate_slab_order(cachep, size, flags); > - if (!cachep->num) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -/** > - * __kmem_cache_create - Create a cache. > - * @cachep: cache management descriptor > - * @flags: SLAB flags > - * > - * Returns a ptr to the cache on success, NULL on failure. > - * Cannot be called within an int, but can be interrupted. > - * The @ctor is run when new pages are allocated by the cache. > - * > - * The flags are > - * > - * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) > - * to catch references to uninitialised memory. > - * > - * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check > - * for buffer overruns. > - * > - * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware > - * cacheline. This can be beneficial if you're counting cycles as closely > - * as davem. > - * > - * Return: a pointer to the created cache or %NULL in case of error > - */ > -int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) > -{ > - size_t ralign = BYTES_PER_WORD; > - gfp_t gfp; > - int err; > - unsigned int size = cachep->size; > - > -#if DEBUG > -#if FORCED_DEBUG > - /* > - * Enable redzoning and last user accounting, except for caches with > - * large objects, if the increased size would increase the object size > - * above the next power of two: caches with object sizes just above a > - * power of two have a significant amount of internal fragmentation. > - */ > - if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + > - 2 * sizeof(unsigned long long))) > - flags |= SLAB_RED_ZONE | SLAB_STORE_USER; > - if (!(flags & SLAB_TYPESAFE_BY_RCU)) > - flags |= SLAB_POISON; > -#endif > -#endif > - > - /* > - * Check that size is in terms of words. This is needed to avoid > - * unaligned accesses for some archs when redzoning is used, and makes > - * sure any on-slab bufctl's are also correctly aligned. > - */ > - size = ALIGN(size, BYTES_PER_WORD); > - > - if (flags & SLAB_RED_ZONE) { > - ralign = REDZONE_ALIGN; > - /* If redzoning, ensure that the second redzone is suitably > - * aligned, by adjusting the object size accordingly. */ > - size = ALIGN(size, REDZONE_ALIGN); > - } > - > - /* 3) caller mandated alignment */ > - if (ralign < cachep->align) { > - ralign = cachep->align; > - } > - /* disable debug if necessary */ > - if (ralign > __alignof__(unsigned long long)) > - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > - /* > - * 4) Store it. > - */ > - cachep->align = ralign; > - cachep->colour_off = cache_line_size(); > - /* Offset must be a multiple of the alignment. */ > - if (cachep->colour_off < cachep->align) > - cachep->colour_off = cachep->align; > - > - if (slab_is_available()) > - gfp = GFP_KERNEL; > - else > - gfp = GFP_NOWAIT; > - > -#if DEBUG > - > - /* > - * Both debugging options require word-alignment which is calculated > - * into align above. > - */ > - if (flags & SLAB_RED_ZONE) { > - /* add space for red zone words */ > - cachep->obj_offset += sizeof(unsigned long long); > - size += 2 * sizeof(unsigned long long); > - } > - if (flags & SLAB_STORE_USER) { > - /* user store requires one word storage behind the end of > - * the real object. But if the second red zone needs to be > - * aligned to 64 bits, we must allow that much space. > - */ > - if (flags & SLAB_RED_ZONE) > - size += REDZONE_ALIGN; > - else > - size += BYTES_PER_WORD; > - } > -#endif > - > - kasan_cache_create(cachep, &size, &flags); > - > - size = ALIGN(size, cachep->align); > - /* > - * We should restrict the number of objects in a slab to implement > - * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition. > - */ > - if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE) > - size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align); > - > -#if DEBUG > - /* > - * To activate debug pagealloc, off-slab management is necessary > - * requirement. In early phase of initialization, small sized slab > - * doesn't get initialized so it would not be possible. So, we need > - * to check size >= 256. It guarantees that all necessary small > - * sized slab is initialized in current slab initialization sequence. > - */ > - if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) && > - size >= 256 && cachep->object_size > cache_line_size()) { > - if (size < PAGE_SIZE || size % PAGE_SIZE == 0) { > - size_t tmp_size = ALIGN(size, PAGE_SIZE); > - > - if (set_off_slab_cache(cachep, tmp_size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - cachep->obj_offset += tmp_size - size; > - size = tmp_size; > - goto done; > - } > - } > - } > -#endif > - > - if (set_objfreelist_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OBJFREELIST_SLAB; > - goto done; > - } > - > - if (set_off_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - goto done; > - } > - > - if (set_on_slab_cache(cachep, size, flags)) > - goto done; > - > - return -E2BIG; > - > -done: > - cachep->freelist_size = cachep->num * sizeof(freelist_idx_t); > - cachep->flags = flags; > - cachep->allocflags = __GFP_COMP; > - if (flags & SLAB_CACHE_DMA) > - cachep->allocflags |= GFP_DMA; > - if (flags & SLAB_CACHE_DMA32) > - cachep->allocflags |= GFP_DMA32; > - if (flags & SLAB_RECLAIM_ACCOUNT) > - cachep->allocflags |= __GFP_RECLAIMABLE; > - cachep->size = size; > - cachep->reciprocal_buffer_size = reciprocal_value(size); > - > -#if DEBUG > - /* > - * If we're going to use the generic kernel_map_pages() > - * poisoning, then it's going to smash the contents of > - * the redzone and userword anyhow, so switch them off. > - */ > - if (IS_ENABLED(CONFIG_PAGE_POISONING) && > - (cachep->flags & SLAB_POISON) && > - is_debug_pagealloc_cache(cachep)) > - cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > -#endif > - > - err = setup_cpu_cache(cachep, gfp); > - if (err) { > - __kmem_cache_release(cachep); > - return err; > - } > - > - return 0; > -} > - > -#if DEBUG > -static void check_irq_off(void) > -{ > - BUG_ON(!irqs_disabled()); > -} > - > -static void check_irq_on(void) > -{ > - BUG_ON(irqs_disabled()); > -} > - > -static void check_mutex_acquired(void) > -{ > - BUG_ON(!mutex_is_locked(&slab_mutex)); > -} > - > -static void check_spinlock_acquired(struct kmem_cache *cachep) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); > -#endif > -} > - > -static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, node)->list_lock); > -#endif > -} > - > -#else > -#define check_irq_off() do { } while(0) > -#define check_irq_on() do { } while(0) > -#define check_mutex_acquired() do { } while(0) > -#define check_spinlock_acquired(x) do { } while(0) > -#define check_spinlock_acquired_node(x, y) do { } while(0) > -#endif > - > -static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, > - int node, bool free_all, struct list_head *list) > -{ > - int tofree; > - > - if (!ac || !ac->avail) > - return; > - > - tofree = free_all ? ac->avail : (ac->limit + 4) / 5; > - if (tofree > ac->avail) > - tofree = (ac->avail + 1) / 2; > - > - free_block(cachep, ac->entry, tofree, node, list); > - ac->avail -= tofree; > - memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); > -} > - > -static void do_drain(void *arg) > -{ > - struct kmem_cache *cachep = arg; > - struct array_cache *ac; > - int node = numa_mem_id(); > - struct kmem_cache_node *n; > - LIST_HEAD(list); > - > - check_irq_off(); > - ac = cpu_cache_get(cachep); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock(&n->list_lock); > - ac->avail = 0; > - slabs_destroy(cachep, &list); > -} > - > -static void drain_cpu_caches(struct kmem_cache *cachep) > -{ > - struct kmem_cache_node *n; > - int node; > - LIST_HEAD(list); > - > - on_each_cpu(do_drain, cachep, 1); > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) > - if (n->alien) > - drain_alien_cache(cachep, n->alien); > - > - for_each_kmem_cache_node(cachep, node, n) { > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, n->shared, node, true, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > - } > -} > - > -/* > - * Remove slabs from the list of free slabs. > - * Specify the number of slabs to drain in tofree. > - * > - * Returns the actual number of slabs released. > - */ > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree) > -{ > - struct list_head *p; > - int nr_freed; > - struct slab *slab; > - > - nr_freed = 0; > - while (nr_freed < tofree && !list_empty(&n->slabs_free)) { > - > - raw_spin_lock_irq(&n->list_lock); > - p = n->slabs_free.prev; > - if (p == &n->slabs_free) { > - raw_spin_unlock_irq(&n->list_lock); > - goto out; > - } > - > - slab = list_entry(p, struct slab, slab_list); > - list_del(&slab->slab_list); > - n->free_slabs--; > - n->total_slabs--; > - /* > - * Safe to drop the lock. The slab is no longer linked > - * to the cache. > - */ > - n->free_objects -= cache->num; > - raw_spin_unlock_irq(&n->list_lock); > - slab_destroy(cache, slab); > - nr_freed++; > - > - cond_resched(); > - } > -out: > - return nr_freed; > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) > - return false; > - return true; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *cachep) > -{ > - int ret = 0; > - int node; > - struct kmem_cache_node *n; > - > - drain_cpu_caches(cachep); > - > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) { > - drain_freelist(cachep, n, INT_MAX); > - > - ret += !list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial); > - } > - return (ret ? 1 : 0); > -} > - > -int __kmem_cache_shutdown(struct kmem_cache *cachep) > -{ > - return __kmem_cache_shrink(cachep); > -} > - > -void __kmem_cache_release(struct kmem_cache *cachep) > -{ > - int i; > - struct kmem_cache_node *n; > - > - cache_random_seq_destroy(cachep); > - > - free_percpu(cachep->cpu_cache); > - > - /* NUMA: free the node structures */ > - for_each_kmem_cache_node(cachep, i, n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[i] = NULL; > - } > -} > - > -/* > - * Get the memory for a slab management obj. > - * > - * For a slab cache when the slab descriptor is off-slab, the > - * slab descriptor can't come from the same cache which is being created, > - * Because if it is the case, that means we defer the creation of > - * the kmalloc_{dma,}_cache of size sizeof(slab descriptor) to this point. > - * And we eventually call down to __kmem_cache_create(), which > - * in turn looks up in the kmalloc_{dma,}_caches for the desired-size one. > - * This is a "chicken-and-egg" problem. > - * > - * So the off-slab slab descriptor shall come from the kmalloc_{dma,}_caches, > - * which are all initialized during kmem_cache_init(). > - */ > -static void *alloc_slabmgmt(struct kmem_cache *cachep, > - struct slab *slab, int colour_off, > - gfp_t local_flags, int nodeid) > -{ > - void *freelist; > - void *addr = slab_address(slab); > - > - slab->s_mem = addr + colour_off; > - slab->active = 0; > - > - if (OBJFREELIST_SLAB(cachep)) > - freelist = NULL; > - else if (OFF_SLAB(cachep)) { > - /* Slab management obj is off-slab. */ > - freelist = kmalloc_node(cachep->freelist_size, > - local_flags, nodeid); > - } else { > - /* We will use last bytes at the slab for freelist */ > - freelist = addr + (PAGE_SIZE << cachep->gfporder) - > - cachep->freelist_size; > - } > - > - return freelist; > -} > - > -static inline freelist_idx_t get_free_obj(struct slab *slab, unsigned int idx) > -{ > - return ((freelist_idx_t *) slab->freelist)[idx]; > -} > - > -static inline void set_free_obj(struct slab *slab, > - unsigned int idx, freelist_idx_t val) > -{ > - ((freelist_idx_t *)(slab->freelist))[idx] = val; > -} > - > -static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab) > -{ > -#if DEBUG > - int i; > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = NULL; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - /* > - * Constructors are not allowed to allocate memory from the same > - * cache which they are a constructor for. Otherwise, deadlock. > - * They must also be threaded. > - */ > - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { > - kasan_unpoison_object_data(cachep, > - objp + obj_offset(cachep)); > - cachep->ctor(objp + obj_offset(cachep)); > - kasan_poison_object_data( > - cachep, objp + obj_offset(cachep)); > - } > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the end of an object"); > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the start of an object"); > - } > - /* need to poison the objs? */ > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - } > -#endif > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Hold information during a freelist initialization */ > -union freelist_init_state { > - struct { > - unsigned int pos; > - unsigned int *list; > - unsigned int count; > - }; > - struct rnd_state rnd_state; > -}; > - > -/* > - * Initialize the state based on the randomization method available. > - * return true if the pre-computed list is available, false otherwise. > - */ > -static bool freelist_state_initialize(union freelist_init_state *state, > - struct kmem_cache *cachep, > - unsigned int count) > -{ > - bool ret; > - unsigned int rand; > - > - /* Use best entropy available to define a random shift */ > - rand = get_random_u32(); > - > - /* Use a random state if the pre-computed list is not available */ > - if (!cachep->random_seq) { > - prandom_seed_state(&state->rnd_state, rand); > - ret = false; > - } else { > - state->list = cachep->random_seq; > - state->count = count; > - state->pos = rand % count; > - ret = true; > - } > - return ret; > -} > - > -/* Get the next entry on the list and randomize it using a random shift */ > -static freelist_idx_t next_random_slot(union freelist_init_state *state) > -{ > - if (state->pos >= state->count) > - state->pos = 0; > - return state->list[state->pos++]; > -} > - > -/* Swap two freelist entries */ > -static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b) > -{ > - swap(((freelist_idx_t *) slab->freelist)[a], > - ((freelist_idx_t *) slab->freelist)[b]); > -} > - > -/* > - * Shuffle the freelist initialization state based on pre-computed lists. > - * return true if the list was successfully shuffled, false otherwise. > - */ > -static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab) > -{ > - unsigned int objfreelist = 0, i, rand, count = cachep->num; > - union freelist_init_state state; > - bool precomputed; > - > - if (count < 2) > - return false; > - > - precomputed = freelist_state_initialize(&state, cachep, count); > - > - /* Take a random entry as the objfreelist */ > - if (OBJFREELIST_SLAB(cachep)) { > - if (!precomputed) > - objfreelist = count - 1; > - else > - objfreelist = next_random_slot(&state); > - slab->freelist = index_to_obj(cachep, slab, objfreelist) + > - obj_offset(cachep); > - count--; > - } > - > - /* > - * On early boot, generate the list dynamically. > - * Later use a pre-computed list for speed. > - */ > - if (!precomputed) { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, i); > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(&state.rnd_state); > - rand %= (i + 1); > - swap_free_obj(slab, i, rand); > - } > - } else { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, next_random_slot(&state)); > - } > - > - if (OBJFREELIST_SLAB(cachep)) > - set_free_obj(slab, cachep->num - 1, objfreelist); > - > - return true; > -} > -#else > -static inline bool shuffle_freelist(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static void cache_init_objs(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - void *objp; > - bool shuffled; > - > - cache_init_objs_debug(cachep, slab); > - > - /* Try to randomize the freelist if enabled */ > - shuffled = shuffle_freelist(cachep, slab); > - > - if (!shuffled && OBJFREELIST_SLAB(cachep)) { > - slab->freelist = index_to_obj(cachep, slab, cachep->num - 1) + > - obj_offset(cachep); > - } > - > - for (i = 0; i < cachep->num; i++) { > - objp = index_to_obj(cachep, slab, i); > - objp = kasan_init_slab_obj(cachep, objp); > - > - /* constructor could break poison info */ > - if (DEBUG == 0 && cachep->ctor) { > - kasan_unpoison_object_data(cachep, objp); > - cachep->ctor(objp); > - kasan_poison_object_data(cachep, objp); > - } > - > - if (!shuffled) > - set_free_obj(slab, i, i); > - } > -} > - > -static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *objp; > - > - objp = index_to_obj(cachep, slab, get_free_obj(slab, slab->active)); > - slab->active++; > - > - return objp; > -} > - > -static void slab_put_obj(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - unsigned int objnr = obj_to_index(cachep, slab, objp); > -#if DEBUG > - unsigned int i; > - > - /* Verify double free bug */ > - for (i = slab->active; i < cachep->num; i++) { > - if (get_free_obj(slab, i) == objnr) { > - pr_err("slab: double free detected in cache '%s', objp %px\n", > - cachep->name, objp); > - BUG(); > - } > - } > -#endif > - slab->active--; > - if (!slab->freelist) > - slab->freelist = objp + obj_offset(cachep); > - > - set_free_obj(slab, slab->active, objnr); > -} > - > -/* > - * Grow (by 1) the number of slabs within a cache. This is called by > - * kmem_cache_alloc() when there are no active objs left in a cache. > - */ > -static struct slab *cache_grow_begin(struct kmem_cache *cachep, > - gfp_t flags, int nodeid) > -{ > - void *freelist; > - size_t offset; > - gfp_t local_flags; > - int slab_node; > - struct kmem_cache_node *n; > - struct slab *slab; > - > - /* > - * Be lazy and only check for valid flags here, keeping it out of the > - * critical path in kmem_cache_alloc(). > - */ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); > - > - check_irq_off(); > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_enable(); > - > - /* > - * Get mem for the objs. Attempt to allocate a physical page from > - * 'nodeid'. > - */ > - slab = kmem_getpages(cachep, local_flags, nodeid); > - if (!slab) > - goto failed; > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - /* Get colour for the slab, and cal the next value. */ > - n->colour_next++; > - if (n->colour_next >= cachep->colour) > - n->colour_next = 0; > - > - offset = n->colour_next; > - if (offset >= cachep->colour) > - offset = 0; > - > - offset *= cachep->colour_off; > - > - /* > - * Call kasan_poison_slab() before calling alloc_slabmgmt(), so > - * page_address() in the latter returns a non-tagged pointer, > - * as it should be for slab pages. > - */ > - kasan_poison_slab(slab); > - > - /* Get slab management. */ > - freelist = alloc_slabmgmt(cachep, slab, offset, > - local_flags & ~GFP_CONSTRAINT_MASK, slab_node); > - if (OFF_SLAB(cachep) && !freelist) > - goto opps1; > - > - slab->slab_cache = cachep; > - slab->freelist = freelist; > - > - cache_init_objs(cachep, slab); > - > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - > - return slab; > - > -opps1: > - kmem_freepages(cachep, slab); > -failed: > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - return NULL; > -} > - > -static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) > -{ > - struct kmem_cache_node *n; > - void *list = NULL; > - > - check_irq_off(); > - > - if (!slab) > - return; > - > - INIT_LIST_HEAD(&slab->slab_list); > - n = get_node(cachep, slab_nid(slab)); > - > - raw_spin_lock(&n->list_lock); > - n->total_slabs++; > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - fixup_slab_list(cachep, n, slab, &list); > - > - STATS_INC_GROWN(cachep); > - n->free_objects += cachep->num - slab->active; > - raw_spin_unlock(&n->list_lock); > - > - fixup_objfreelist_debug(cachep, &list); > -} > - > -#if DEBUG > - > -/* > - * Perform extra freeing checks: > - * - detect bad pointers. > - * - POISON/RED_ZONE checking > - */ > -static void kfree_debugcheck(const void *objp) > -{ > - if (!virt_addr_valid(objp)) { > - pr_err("kfree_debugcheck: out of range ptr %lxh\n", > - (unsigned long)objp); > - BUG(); > - } > -} > - > -static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) > -{ > - unsigned long long redzone1, redzone2; > - > - redzone1 = *dbg_redzone1(cache, obj); > - redzone2 = *dbg_redzone2(cache, obj); > - > - /* > - * Redzone is ok. > - */ > - if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) > - return; > - > - if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) > - slab_error(cache, "double free detected"); > - else > - slab_error(cache, "memory outside object was overwritten"); > - > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - obj, redzone1, redzone2); > -} > - > -static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned int objnr; > - struct slab *slab; > - > - BUG_ON(virt_to_cache(objp) != cachep); > - > - objp -= obj_offset(cachep); > - kfree_debugcheck(objp); > - slab = virt_to_slab(objp); > - > - if (cachep->flags & SLAB_RED_ZONE) { > - verify_redzone_free(cachep, objp); > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - objnr = obj_to_index(cachep, slab, objp); > - > - BUG_ON(objnr >= cachep->num); > - BUG_ON(objp != index_to_obj(cachep, slab, objnr)); > - > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - return objp; > -} > - > -#else > -#define kfree_debugcheck(x) do { } while(0) > -#define cache_free_debugcheck(x, objp, z) (objp) > -#endif > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list) > -{ > -#if DEBUG > - void *next = *list; > - void *objp; > - > - while (next) { > - objp = next - obj_offset(cachep); > - next = *(void **)next; > - poison_obj(cachep, objp, POISON_FREE); > - } > -#endif > -} > - > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list) > -{ > - /* move slabp to correct slabp list: */ > - list_del(&slab->slab_list); > - if (slab->active == cachep->num) { > - list_add(&slab->slab_list, &n->slabs_full); > - if (OBJFREELIST_SLAB(cachep)) { > -#if DEBUG > - /* Poisoning will be done without holding the lock */ > - if (cachep->flags & SLAB_POISON) { > - void **objp = slab->freelist; > - > - *objp = *list; > - *list = objp; > - } > -#endif > - slab->freelist = NULL; > - } > - } else > - list_add(&slab->slab_list, &n->slabs_partial); > -} > - > -/* Try to find non-pfmemalloc slab if needed */ > -static noinline struct slab *get_valid_first_slab(struct kmem_cache_node *n, > - struct slab *slab, bool pfmemalloc) > -{ > - if (!slab) > - return NULL; > - > - if (pfmemalloc) > - return slab; > - > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - > - /* No need to keep pfmemalloc slab if we have enough free objects */ > - if (n->free_objects > n->free_limit) { > - slab_clear_pfmemalloc(slab); > - return slab; > - } > - > - /* Move pfmemalloc slab to the end of list to speed up next search */ > - list_del(&slab->slab_list); > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - > - list_for_each_entry(slab, &n->slabs_partial, slab_list) { > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - } > - > - n->free_touched = 1; > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - if (!slab_test_pfmemalloc(slab)) { > - n->free_slabs--; > - return slab; > - } > - } > - > - return NULL; > -} > - > -static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) > -{ > - struct slab *slab; > - > - assert_raw_spin_locked(&n->list_lock); > - slab = list_first_entry_or_null(&n->slabs_partial, struct slab, > - slab_list); > - if (!slab) { > - n->free_touched = 1; > - slab = list_first_entry_or_null(&n->slabs_free, struct slab, > - slab_list); > - if (slab) > - n->free_slabs--; > - } > - > - if (sk_memalloc_socks()) > - slab = get_valid_first_slab(n, slab, pfmemalloc); > - > - return slab; > -} > - > -static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, > - struct kmem_cache_node *n, gfp_t flags) > -{ > - struct slab *slab; > - void *obj; > - void *list = NULL; > - > - if (!gfp_pfmemalloc_allowed(flags)) > - return NULL; > - > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, true); > - if (!slab) { > - raw_spin_unlock(&n->list_lock); > - return NULL; > - } > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > - return obj; > -} > - > -/* > - * Slab list should be fixed up by fixup_slab_list() for existing slab > - * or cache_grow_end() for new slab > - */ > -static __always_inline int alloc_block(struct kmem_cache *cachep, > - struct array_cache *ac, struct slab *slab, int batchcount) > -{ > - /* > - * There must be at least one object available for > - * allocation. > - */ > - BUG_ON(slab->active >= cachep->num); > - > - while (slab->active < cachep->num && batchcount--) { > - STATS_INC_ALLOCED(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - ac->entry[ac->avail++] = slab_get_obj(cachep, slab); > - } > - > - return batchcount; > -} > - > -static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - struct array_cache *ac, *shared; > - int node; > - void *list = NULL; > - struct slab *slab; > - > - check_irq_off(); > - node = numa_mem_id(); > - > - ac = cpu_cache_get(cachep); > - batchcount = ac->batchcount; > - if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { > - /* > - * If there was little recent activity on this cache, then > - * perform only a partial refill. Otherwise we could generate > - * refill bouncing. > - */ > - batchcount = BATCHREFILL_LIMIT; > - } > - n = get_node(cachep, node); > - > - BUG_ON(ac->avail > 0 || !n); > - shared = READ_ONCE(n->shared); > - if (!n->free_objects && (!shared || !shared->avail)) > - goto direct_grow; > - > - raw_spin_lock(&n->list_lock); > - shared = READ_ONCE(n->shared); > - > - /* See if we can refill from the shared array */ > - if (shared && transfer_objects(ac, shared, batchcount)) { > - shared->touched = 1; > - goto alloc_done; > - } > - > - while (batchcount > 0) { > - /* Get slab alloc is to come from. */ > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired(cachep); > - > - batchcount = alloc_block(cachep, ac, slab, batchcount); > - fixup_slab_list(cachep, n, slab, &list); > - } > - > -must_grow: > - n->free_objects -= ac->avail; > -alloc_done: > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > -direct_grow: > - if (unlikely(!ac->avail)) { > - /* Check if we can use obj in pfmemalloc slab */ > - if (sk_memalloc_socks()) { > - void *obj = cache_alloc_pfmemalloc(cachep, n, flags); > - > - if (obj) > - return obj; > - } > - > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), node); > - > - /* > - * cache_grow_begin() can reenable interrupts, > - * then ac could change. > - */ > - ac = cpu_cache_get(cachep); > - if (!ac->avail && slab) > - alloc_block(cachep, ac, slab, batchcount); > - cache_grow_end(cachep, slab); > - > - if (!ac->avail) > - return NULL; > - } > - ac->touched = 1; > - > - return ac->entry[--ac->avail]; > -} > - > -#if DEBUG > -static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, > - gfp_t flags, void *objp, unsigned long caller) > -{ > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - if (!objp || is_kfence_address(objp)) > - return objp; > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - poison_obj(cachep, objp, POISON_INUSE); > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || > - *dbg_redzone2(cachep, objp) != RED_INACTIVE) { > - slab_error(cachep, "double free, or memory outside object was overwritten"); > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - objp, *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - *dbg_redzone1(cachep, objp) = RED_ACTIVE; > - *dbg_redzone2(cachep, objp) = RED_ACTIVE; > - } > - > - objp += obj_offset(cachep); > - if (cachep->ctor && cachep->flags & SLAB_POISON) > - cachep->ctor(objp); > - if ((unsigned long)objp & (arch_slab_minalign() - 1)) { > - pr_err("0x%px: not aligned to arch_slab_minalign()=%u\n", objp, > - arch_slab_minalign()); > - } > - return objp; > -} > -#else > -#define cache_alloc_debugcheck_after(a, b, objp, d) (objp) > -#endif > - > -static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - void *objp; > - struct array_cache *ac; > - > - check_irq_off(); > - > - ac = cpu_cache_get(cachep); > - if (likely(ac->avail)) { > - ac->touched = 1; > - objp = ac->entry[--ac->avail]; > - > - STATS_INC_ALLOCHIT(cachep); > - goto out; > - } > - > - STATS_INC_ALLOCMISS(cachep); > - objp = cache_alloc_refill(cachep, flags); > - /* > - * the 'ac' may be updated by cache_alloc_refill(), > - * and kmemleak_erase() requires its correct value. > - */ > - ac = cpu_cache_get(cachep); > - > -out: > - /* > - * To avoid a false negative, if an object that is in one of the > - * per-CPU caches is leaked, we need to make sure kmemleak doesn't > - * treat the array pointers as a reference to the object. > - */ > - if (objp) > - kmemleak_erase(&ac->entry[ac->avail]); > - return objp; > -} > - > -#ifdef CONFIG_NUMA > -static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); > - > -/* > - * Try allocating on another node if PFA_SPREAD_SLAB is a mempolicy is set. > - * > - * If we are in_interrupt, then process context, including cpusets and > - * mempolicy, may not apply and should not be used for allocation policy. > - */ > -static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - int nid_alloc, nid_here; > - > - if (in_interrupt() || (flags & __GFP_THISNODE)) > - return NULL; > - nid_alloc = nid_here = numa_mem_id(); > - if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) > - nid_alloc = cpuset_slab_spread_node(); > - else if (current->mempolicy) > - nid_alloc = mempolicy_slab_node(); > - if (nid_alloc != nid_here) > - return ____cache_alloc_node(cachep, flags, nid_alloc); > - return NULL; > -} > - > -/* > - * Fallback function if there was no memory available and no objects on a > - * certain node and fall back is permitted. First we scan all the > - * available node for available objects. If that fails then we > - * perform an allocation without specifying a node. This allows the page > - * allocator to do its reclaim / fallback magic. We then insert the > - * slab into the proper nodelist and then allocate from it. > - */ > -static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) > -{ > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(flags); > - void *obj = NULL; > - struct slab *slab; > - int nid; > - unsigned int cpuset_mems_cookie; > - > - if (flags & __GFP_THISNODE) > - return NULL; > - > -retry_cpuset: > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), flags); > - > -retry: > - /* > - * Look through allowed nodes for objects available > - * from existing per node queues. > - */ > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - nid = zone_to_nid(zone); > - > - if (cpuset_zone_allowed(zone, flags) && > - get_node(cache, nid) && > - get_node(cache, nid)->free_objects) { > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - if (obj) > - break; > - } > - } > - > - if (!obj) { > - /* > - * This allocation will be performed within the constraints > - * of the current cpuset / memory policy requirements. > - * We may trigger various forms of reclaim on the allowed > - * set and go into memory reserves if necessary. > - */ > - slab = cache_grow_begin(cache, flags, numa_mem_id()); > - cache_grow_end(cache, slab); > - if (slab) { > - nid = slab_nid(slab); > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - > - /* > - * Another processor may allocate the objects in > - * the slab since we are not holding any locks. > - */ > - if (!obj) > - goto retry; > - } > - } > - > - if (unlikely(!obj && read_mems_allowed_retry(cpuset_mems_cookie))) > - goto retry_cpuset; > - return obj; > -} > - > -/* > - * An interface to enable slab creation on nodeid > - */ > -static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - void *obj = NULL; > - void *list = NULL; > - > - VM_BUG_ON(nodeid < 0 || nodeid >= MAX_NUMNODES); > - n = get_node(cachep, nodeid); > - BUG_ON(!n); > - > - check_irq_off(); > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired_node(cachep, nodeid); > - > - STATS_INC_NODEALLOCS(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - BUG_ON(slab->active == cachep->num); > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - return obj; > - > -must_grow: > - raw_spin_unlock(&n->list_lock); > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); > - if (slab) { > - /* This slab isn't counted yet so don't update free_objects */ > - obj = slab_get_obj(cachep, slab); > - } > - cache_grow_end(cachep, slab); > - > - return obj ? obj : fallback_alloc(cachep, flags); > -} > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *objp = NULL; > - int slab_node = numa_mem_id(); > - > - if (nodeid == NUMA_NO_NODE) { > - if (current->mempolicy || cpuset_do_slab_mem_spread()) { > - objp = alternate_node_alloc(cachep, flags); > - if (objp) > - goto out; > - } > - /* > - * Use the locally cached objects if possible. > - * However ____cache_alloc does not allow fallback > - * to other nodes. It may fail while we still have > - * objects on other nodes available. > - */ > - objp = ____cache_alloc(cachep, flags); > - nodeid = slab_node; > - } else if (nodeid == slab_node) { > - objp = ____cache_alloc(cachep, flags); > - } else if (!get_node(cachep, nodeid)) { > - /* Node not bootstrapped yet */ > - objp = fallback_alloc(cachep, flags); > - goto out; > - } > - > - /* > - * We may just have run out of memory on the local node. > - * ____cache_alloc_node() knows how to locate memory on other nodes > - */ > - if (!objp) > - objp = ____cache_alloc_node(cachep, flags, nodeid); > -out: > - return objp; > -} > -#else > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid __maybe_unused) > -{ > - return ____cache_alloc(cachep, flags); > -} > - > -#endif /* CONFIG_NUMA */ > - > -static __always_inline void * > -slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - int nodeid, size_t orig_size, unsigned long caller) > -{ > - unsigned long save_flags; > - void *objp; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - flags &= gfp_allowed_mask; > - cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); > - if (unlikely(!cachep)) > - return NULL; > - > - objp = kfence_alloc(cachep, orig_size, flags); > - if (unlikely(objp)) > - goto out; > - > - local_irq_save(save_flags); > - objp = __do_cache_alloc(cachep, flags, nodeid); > - local_irq_restore(save_flags); > - objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); > - prefetchw(objp); > - init = slab_want_init_on_alloc(flags, cachep); > - > -out: > - slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init, > - cachep->object_size); > - return objp; > -} > - > -static __always_inline void * > -slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - size_t orig_size, unsigned long caller) > -{ > - return slab_alloc_node(cachep, lru, flags, NUMA_NO_NODE, orig_size, > - caller); > -} > - > -/* > - * Caller needs to acquire correct kmem_cache_node's list_lock > - * @list: List of detached free slabs should be freed by caller > - */ > -static void free_block(struct kmem_cache *cachep, void **objpp, > - int nr_objects, int node, struct list_head *list) > -{ > - int i; > - struct kmem_cache_node *n = get_node(cachep, node); > - struct slab *slab; > - > - n->free_objects += nr_objects; > - > - for (i = 0; i < nr_objects; i++) { > - void *objp; > - struct slab *slab; > - > - objp = objpp[i]; > - > - slab = virt_to_slab(objp); > - list_del(&slab->slab_list); > - check_spinlock_acquired_node(cachep, node); > - slab_put_obj(cachep, slab, objp); > - STATS_DEC_ACTIVE(cachep); > - > - /* fixup slab chains */ > - if (slab->active == 0) { > - list_add(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else { > - /* Unconditionally move a slab to the end of the > - * partial list on free - maximum time for the > - * other objects to be freed, too. > - */ > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - } > - } > - > - while (n->free_objects > n->free_limit && !list_empty(&n->slabs_free)) { > - n->free_objects -= cachep->num; > - > - slab = list_last_entry(&n->slabs_free, struct slab, slab_list); > - list_move(&slab->slab_list, list); > - n->free_slabs--; > - n->total_slabs--; > - } > -} > - > -static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - LIST_HEAD(list); > - > - batchcount = ac->batchcount; > - > - check_irq_off(); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - if (n->shared) { > - struct array_cache *shared_array = n->shared; > - int max = shared_array->limit - shared_array->avail; > - if (max) { > - if (batchcount > max) > - batchcount = max; > - memcpy(&(shared_array->entry[shared_array->avail]), > - ac->entry, sizeof(void *) * batchcount); > - shared_array->avail += batchcount; > - goto free_done; > - } > - } > - > - free_block(cachep, ac->entry, batchcount, node, &list); > -free_done: > -#if STATS > - { > - int i = 0; > - struct slab *slab; > - > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - BUG_ON(slab->active); > - > - i++; > - } > - STATS_SET_FREEABLE(cachep, i); > - } > -#endif > - raw_spin_unlock(&n->list_lock); > - ac->avail -= batchcount; > - memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Release an obj back to its cache. If the obj has a constructed state, it must > - * be in this state _before_ it is released. Called with disabled ints. > - */ > -static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - bool init; > - > - memcg_slab_free_hook(cachep, virt_to_slab(objp), &objp, 1); > - > - if (is_kfence_address(objp)) { > - kmemleak_free_recursive(objp, cachep->flags); > - __kfence_free(objp); > - return; > - } > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset must be > - * kept together to avoid discrepancies in behavior. > - */ > - init = slab_want_init_on_free(cachep); > - if (init && !kasan_has_integrated_init()) > - memset(objp, 0, cachep->object_size); > - /* KASAN might put objp into memory quarantine, delaying its reuse. */ > - if (kasan_slab_free(cachep, objp, init)) > - return; > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(objp, cachep->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - ___cache_free(cachep, objp, caller); > -} > - > -void ___cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - struct array_cache *ac = cpu_cache_get(cachep); > - > - check_irq_off(); > - kmemleak_free_recursive(objp, cachep->flags); > - objp = cache_free_debugcheck(cachep, objp, caller); > - > - /* > - * Skip calling cache_free_alien() when the platform is not numa. > - * This will avoid cache misses that happen while accessing slabp (which > - * is per page memory reference) to get nodeid. Instead use a global > - * variable to skip the call, which is mostly likely to be present in > - * the cache. > - */ > - if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) > - return; > - > - if (ac->avail < ac->limit) { > - STATS_INC_FREEHIT(cachep); > - } else { > - STATS_INC_FREEMISS(cachep); > - cache_flusharray(cachep, ac); > - } > - > - if (sk_memalloc_socks()) { > - struct slab *slab = virt_to_slab(objp); > - > - if (unlikely(slab_test_pfmemalloc(slab))) { > - cache_free_pfmemalloc(cachep, slab, objp); > - return; > - } > - } > - > - __free_one(ac, objp); > -} > - > -static __always_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, NULL, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, lru, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -static __always_inline void > -cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, unsigned long caller) > -{ > - size_t i; > - > - for (i = 0; i < size; i++) > - p[i] = cache_alloc_debugcheck_after(s, flags, p[i], caller); > -} > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - struct obj_cgroup *objcg = NULL; > - unsigned long irqflags; > - size_t i; > - > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (!s) > - return 0; > - > - local_irq_save(irqflags); > - for (i = 0; i < size; i++) { > - void *objp = kfence_alloc(s, s->object_size, flags) ?: > - __do_cache_alloc(s, flags, NUMA_NO_NODE); > - > - if (unlikely(!objp)) > - goto error; > - p[i] = objp; > - } > - local_irq_restore(irqflags); > - > - cache_alloc_debugcheck_after_bulk(s, flags, size, p, _RET_IP_); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled section. > - */ > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - /* FIXME: Trace call missing. Christoph would like a bulk variant */ > - return size; > -error: > - local_irq_restore(irqflags); > - cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -/** > - * kmem_cache_alloc_node - Allocate an object on the specified node > - * @cachep: The cache to allocate from. > - * @flags: See kmalloc(). > - * @nodeid: node number of the target node. > - * > - * Identical to kmem_cache_alloc but it will allocate memory on the given > - * node, which can improve the performance for cpu bound structures. > - * > - * Fallback to other node is possible if __GFP_THISNODE is not set. > - * > - * Return: pointer to the new object or %NULL in case of error > - */ > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *ret = slab_alloc_node(cachep, NULL, flags, nodeid, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, nodeid); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(cachep, NULL, flags, nodeid, > - orig_size, caller); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - void *objp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - cachep = slab->slab_cache; > - kpp->kp_slab_cache = cachep; > - objp = object - obj_offset(cachep); > - kpp->kp_data_offset = obj_offset(cachep); > - slab = virt_to_slab(objp); > - objnr = obj_to_index(cachep, slab, objp); > - objp = index_to_obj(cachep, slab, objnr); > - kpp->kp_objp = objp; > - if (DEBUG && cachep->flags & SLAB_STORE_USER) > - kpp->kp_ret = *dbg_userword(cachep, objp); > -} > -#endif > - > -static __always_inline > -void __do_kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - debug_check_no_locks_freed(objp, cachep->object_size); > - if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, cachep->object_size); > - __cache_free(cachep, objp, caller); > - local_irq_restore(flags); > -} > - > -void __kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - __do_kmem_cache_free(cachep, objp, caller); > -} > - > -/** > - * kmem_cache_free - Deallocate an object > - * @cachep: The cache the allocation was from. > - * @objp: The previously allocated object. > - * > - * Free an object which was previously allocated from this > - * cache. > - */ > -void kmem_cache_free(struct kmem_cache *cachep, void *objp) > -{ > - cachep = cache_from_obj(cachep, objp); > - if (!cachep) > - return; > - > - trace_kmem_cache_free(_RET_IP_, objp, cachep); > - __do_kmem_cache_free(cachep, objp, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - for (int i = 0; i < size; i++) { > - void *objp = p[i]; > - struct kmem_cache *s; > - > - if (!orig_s) { > - struct folio *folio = virt_to_folio(objp); > - > - /* called via kfree_bulk */ > - if (!folio_test_slab(folio)) { > - local_irq_restore(flags); > - free_large_kmalloc(folio, objp); > - local_irq_save(flags); > - continue; > - } > - s = folio_slab(folio)->slab_cache; > - } else { > - s = cache_from_obj(orig_s, objp); > - } > - > - if (!s) > - continue; > - > - debug_check_no_locks_freed(objp, s->object_size); > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, s->object_size); > - > - __cache_free(s, objp, _RET_IP_); > - } > - local_irq_restore(flags); > - > - /* FIXME: add tracing */ > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -/* > - * This initializes kmem_cache_node or resizes various caches for all nodes. > - */ > -static int setup_kmem_cache_nodes(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int ret; > - int node; > - struct kmem_cache_node *n; > - > - for_each_online_node(node) { > - ret = setup_kmem_cache_node(cachep, node, gfp, true); > - if (ret) > - goto fail; > - > - } > - > - return 0; > - > -fail: > - if (!cachep->list.next) { > - /* Cache is not active yet. Roll back what we did */ > - node--; > - while (node >= 0) { > - n = get_node(cachep, node); > - if (n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[node] = NULL; > - } > - node--; > - } > - } > - return -ENOMEM; > -} > - > -/* Always called with the slab_mutex held */ > -static int do_tune_cpucache(struct kmem_cache *cachep, int limit, > - int batchcount, int shared, gfp_t gfp) > -{ > - struct array_cache __percpu *cpu_cache, *prev; > - int cpu; > - > - cpu_cache = alloc_kmem_cache_cpus(cachep, limit, batchcount); > - if (!cpu_cache) > - return -ENOMEM; > - > - prev = cachep->cpu_cache; > - cachep->cpu_cache = cpu_cache; > - /* > - * Without a previous cpu_cache there's no need to synchronize remote > - * cpus, so skip the IPIs. > - */ > - if (prev) > - kick_all_cpus_sync(); > - > - check_irq_on(); > - cachep->batchcount = batchcount; > - cachep->limit = limit; > - cachep->shared = shared; > - > - if (!prev) > - goto setup_node; > - > - for_each_online_cpu(cpu) { > - LIST_HEAD(list); > - int node; > - struct kmem_cache_node *n; > - struct array_cache *ac = per_cpu_ptr(prev, cpu); > - > - node = cpu_to_mem(cpu); > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - free_percpu(prev); > - > -setup_node: > - return setup_kmem_cache_nodes(cachep, gfp); > -} > - > -/* Called with slab_mutex held always */ > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int err; > - int limit = 0; > - int shared = 0; > - int batchcount = 0; > - > - err = cache_random_seq_create(cachep, cachep->num, gfp); > - if (err) > - goto end; > - > - /* > - * The head array serves three purposes: > - * - create a LIFO ordering, i.e. return objects that are cache-warm > - * - reduce the number of spinlock operations. > - * - reduce the number of linked list operations on the slab and > - * bufctl chains: array operations are cheaper. > - * The numbers are guessed, we should auto-tune as described by > - * Bonwick. > - */ > - if (cachep->size > 131072) > - limit = 1; > - else if (cachep->size > PAGE_SIZE) > - limit = 8; > - else if (cachep->size > 1024) > - limit = 24; > - else if (cachep->size > 256) > - limit = 54; > - else > - limit = 120; > - > - /* > - * CPU bound tasks (e.g. network routing) can exhibit cpu bound > - * allocation behaviour: Most allocs on one cpu, most free operations > - * on another cpu. For these cases, an efficient object passing between > - * cpus is necessary. This is provided by a shared array. The array > - * replaces Bonwick's magazine layer. > - * On uniprocessor, it's functionally equivalent (but less efficient) > - * to a larger limit. Thus disabled by default. > - */ > - shared = 0; > - if (cachep->size <= PAGE_SIZE && num_possible_cpus() > 1) > - shared = 8; > - > -#if DEBUG > - /* > - * With debugging enabled, large batchcount lead to excessively long > - * periods with disabled local interrupts. Limit the batchcount > - */ > - if (limit > 32) > - limit = 32; > -#endif > - batchcount = (limit + 1) / 2; > - err = do_tune_cpucache(cachep, limit, batchcount, shared, gfp); > -end: > - if (err) > - pr_err("enable_cpucache failed for %s, error %d\n", > - cachep->name, -err); > - return err; > -} > - > -/* > - * Drain an array if it contains any elements taking the node lock only if > - * necessary. Note that the node listlock also protects the array_cache > - * if drain_array() is used on the shared array. > - */ > -static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, > - struct array_cache *ac, int node) > -{ > - LIST_HEAD(list); > - > - /* ac from n->shared can be freed if we don't hold the slab_mutex. */ > - check_mutex_acquired(); > - > - if (!ac || !ac->avail) > - return; > - > - if (ac->touched) { > - ac->touched = 0; > - return; > - } > - > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, ac, node, false, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/** > - * cache_reap - Reclaim memory from caches. > - * @w: work descriptor > - * > - * Called from workqueue/eventd every few seconds. > - * Purpose: > - * - clear the per-cpu caches for this CPU. > - * - return freeable pages to the main free memory pool. > - * > - * If we cannot acquire the cache chain mutex then just give up - we'll try > - * again on the next iteration. > - */ > -static void cache_reap(struct work_struct *w) > -{ > - struct kmem_cache *searchp; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - struct delayed_work *work = to_delayed_work(w); > - > - if (!mutex_trylock(&slab_mutex)) > - /* Give up. Setup the next iteration. */ > - goto out; > - > - list_for_each_entry(searchp, &slab_caches, list) { > - check_irq_on(); > - > - /* > - * We only take the node lock if absolutely necessary and we > - * have established with reasonable certainty that > - * we can do some work if the lock was obtained. > - */ > - n = get_node(searchp, node); > - > - reap_alien(searchp, n); > - > - drain_array(searchp, n, cpu_cache_get(searchp), node); > - > - /* > - * These are racy checks but it does not matter > - * if we skip one check or scan twice. > - */ > - if (time_after(n->next_reap, jiffies)) > - goto next; > - > - n->next_reap = jiffies + REAPTIMEOUT_NODE; > - > - drain_array(searchp, n, n->shared, node); > - > - if (n->free_touched) > - n->free_touched = 0; > - else { > - int freed; > - > - freed = drain_freelist(searchp, n, (n->free_limit + > - 5 * searchp->num - 1) / (5 * searchp->num)); > - STATS_ADD_REAPED(searchp, freed); > - } > -next: > - cond_resched(); > - } > - check_irq_on(); > - mutex_unlock(&slab_mutex); > - next_reap_node(); > -out: > - /* Set up the next iteration */ > - schedule_delayed_work_on(smp_processor_id(), work, > - round_jiffies_relative(REAPTIMEOUT_AC)); > -} > - > -void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) > -{ > - unsigned long active_objs, num_objs, active_slabs; > - unsigned long total_slabs = 0, free_objs = 0, shared_avail = 0; > - unsigned long free_slabs = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(cachep, node, n) { > - check_irq_on(); > - raw_spin_lock_irq(&n->list_lock); > - > - total_slabs += n->total_slabs; > - free_slabs += n->free_slabs; > - free_objs += n->free_objects; > - > - if (n->shared) > - shared_avail += n->shared->avail; > - > - raw_spin_unlock_irq(&n->list_lock); > - } > - num_objs = total_slabs * cachep->num; > - active_slabs = total_slabs - free_slabs; > - active_objs = num_objs - free_objs; > - > - sinfo->active_objs = active_objs; > - sinfo->num_objs = num_objs; > - sinfo->active_slabs = active_slabs; > - sinfo->num_slabs = total_slabs; > - sinfo->shared_avail = shared_avail; > - sinfo->limit = cachep->limit; > - sinfo->batchcount = cachep->batchcount; > - sinfo->shared = cachep->shared; > - sinfo->objects_per_slab = cachep->num; > - sinfo->cache_order = cachep->gfporder; > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *cachep) > -{ > -#if STATS > - { /* node stats */ > - unsigned long high = cachep->high_mark; > - unsigned long allocs = cachep->num_allocations; > - unsigned long grown = cachep->grown; > - unsigned long reaped = cachep->reaped; > - unsigned long errors = cachep->errors; > - unsigned long max_freeable = cachep->max_freeable; > - unsigned long node_allocs = cachep->node_allocs; > - unsigned long node_frees = cachep->node_frees; > - unsigned long overflows = cachep->node_overflow; > - > - seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu %4lu %4lu %4lu %4lu %4lu", > - allocs, high, grown, > - reaped, errors, max_freeable, node_allocs, > - node_frees, overflows); > - } > - /* cpu stats */ > - { > - unsigned long allochit = atomic_read(&cachep->allochit); > - unsigned long allocmiss = atomic_read(&cachep->allocmiss); > - unsigned long freehit = atomic_read(&cachep->freehit); > - unsigned long freemiss = atomic_read(&cachep->freemiss); > - > - seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", > - allochit, allocmiss, freehit, freemiss); > - } > -#endif > -} > - > -#define MAX_SLABINFO_WRITE 128 > -/** > - * slabinfo_write - Tuning for the slab allocator > - * @file: unused > - * @buffer: user buffer > - * @count: data length > - * @ppos: unused > - * > - * Return: %0 on success, negative error code otherwise. > - */ > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; > - int limit, batchcount, shared, res; > - struct kmem_cache *cachep; > - > - if (count > MAX_SLABINFO_WRITE) > - return -EINVAL; > - if (copy_from_user(&kbuf, buffer, count)) > - return -EFAULT; > - kbuf[MAX_SLABINFO_WRITE] = '\0'; > - > - tmp = strchr(kbuf, ' '); > - if (!tmp) > - return -EINVAL; > - *tmp = '\0'; > - tmp++; > - if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) > - return -EINVAL; > - > - /* Find the cache in the chain of caches. */ > - mutex_lock(&slab_mutex); > - res = -EINVAL; > - list_for_each_entry(cachep, &slab_caches, list) { > - if (!strcmp(cachep->name, kbuf)) { > - if (limit < 1 || batchcount < 1 || > - batchcount > limit || shared < 0) { > - res = 0; > - } else { > - res = do_tune_cpucache(cachep, limit, > - batchcount, shared, > - GFP_KERNEL); > - } > - break; > - } > - } > - mutex_unlock(&slab_mutex); > - if (res >= 0) > - res = count; > - return res; > -} > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - unsigned long offset; > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find and validate object. */ > - cachep = slab->slab_cache; > - objnr = obj_to_index(cachep, slab, (void *)ptr); > - BUG_ON(objnr >= cachep->num); > - > - /* Find offset within object. */ > - if (is_kfence_address(ptr)) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = ptr - index_to_obj(cachep, slab, objnr) - obj_offset(cachep); > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= cachep->useroffset && > - offset - cachep->useroffset <= cachep->usersize && > - n <= cachep->useroffset - offset + cachep->usersize) > - return; > - > - usercopy_abort("SLAB object", cachep->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > diff --git a/mm/slab.h b/mm/slab.h > index 43966aa5fadf..53e97b7640e9 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -9,60 +9,12 @@ > struct slab { > unsigned long __page_flags; > > -#if defined(CONFIG_SLAB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - struct list_head slab_list; > - void *freelist; /* array of free object indexes */ > - void *s_mem; /* first object */ > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int active; > - > -#elif defined(CONFIG_SLUB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - union { > - struct list_head slab_list; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct { > - struct slab *next; > - int slabs; /* Nr of slabs left */ > - }; > -#endif > - }; > - /* Double-word boundary */ > - void *freelist; /* first free object */ > - union { > - unsigned long counters; > - struct { > - unsigned inuse:16; > - unsigned objects:15; > - unsigned frozen:1; > - }; > - }; > - }; > - struct rcu_head rcu_head; > - }; > - 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 > - > atomic_t __page_refcount; > #ifdef CONFIG_MEMCG > unsigned long memcg_data; > @@ -72,20 +24,13 @@ 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); > #endif > #undef SLAB_MATCH > static_assert(sizeof(struct slab) <= sizeof(struct page)); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB) > -static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *))); > -#endif > > /** > * folio_slab - Converts from folio to slab. > @@ -200,7 +145,6 @@ 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) > @@ -223,16 +167,6 @@ struct kmem_cache { > struct list_head list; /* List of all slab caches on the system */ > }; > > -#endif /* CONFIG_SLOB */ > - > -#ifdef CONFIG_SLAB > -#include <linux/slab_def.h> > -#endif > - > -#ifdef CONFIG_SLUB > -#include <linux/slub_def.h> > -#endif > - > #include <linux/memcontrol.h> > #include <linux/fault-inject.h> > #include <linux/kasan.h> > @@ -268,26 +202,6 @@ extern struct list_head slab_caches; > /* The slab cache that manages slab cache information */ > extern struct kmem_cache *kmem_cache; > > -/* A table of kmalloc cache names and sizes */ > -extern const struct kmalloc_info_struct { > - const char *name[NR_KMALLOC_TYPES]; > - 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); > - > -/* Find the kmalloc slab corresponding for a certain size */ > -struct kmem_cache *kmalloc_slab(size_t, gfp_t); > - > -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); > > /* Functions provided by the slab allocators */ > @@ -303,14 +217,6 @@ 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 *)) > @@ -321,15 +227,10 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, > { > 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 */ > @@ -337,26 +238,9 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s) > SLAB_CACHE_DMA32 | SLAB_PANIC | \ > SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) > > -#if defined(CONFIG_DEBUG_SLAB) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > -#elif defined(CONFIG_SLUB_DEBUG) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ > - SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) > -#else > #define SLAB_DEBUG_FLAGS (0) > -#endif > > -#if defined(CONFIG_SLAB) > -#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ > - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ > - SLAB_ACCOUNT) > -#elif defined(CONFIG_SLUB) > -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ > - SLAB_TEMPORARY | SLAB_ACCOUNT | \ > - SLAB_NO_USER_FLAGS | SLAB_KMALLOC) > -#else > #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) > -#endif > > /* Common flags available with current configuration */ > #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) > @@ -409,19 +293,6 @@ static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) > NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; > } > > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -extern void print_tracking(struct kmem_cache *s, void *object); > -long validate_slab_cache(struct kmem_cache *s); > -static inline bool __slub_debug_enabled(void) > -{ > - return static_branch_unlikely(&slub_debug_enabled); > -} > -#else > static inline void print_tracking(struct kmem_cache *s, void *object) > { > } > @@ -429,7 +300,6 @@ static inline bool __slub_debug_enabled(void) > { > return false; > } > -#endif > > /* > * Returns true if any of the specified slub_debug flags is enabled for the > @@ -438,160 +308,9 @@ static inline bool __slub_debug_enabled(void) > */ > static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) > { > - if (IS_ENABLED(CONFIG_SLUB_DEBUG)) > - VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); > - if (__slub_debug_enabled()) > - return s->flags & flags; > return false; > } > > -#ifdef CONFIG_MEMCG_KMEM > -/* > - * slab_objcgs - get the object cgroups vector associated with a slab > - * @slab: a pointer to the slab struct > - * > - * Returns a pointer to the object cgroups vector associated with the slab, > - * or NULL if no such vector has been associated yet. > - */ > -static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > -{ > - unsigned long memcg_data = READ_ONCE(slab->memcg_data); > - > - VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), > - slab_page(slab)); > - VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); > - > - return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); > -} > - > -int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, > - gfp_t gfp, bool new_slab); > -void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, > - enum node_stat_item idx, int nr); > - > -static inline void memcg_free_slab_cgroups(struct slab *slab) > -{ > - kfree(slab_objcgs(slab)); > - slab->memcg_data = 0; > -} > - > -static inline size_t obj_full_size(struct kmem_cache *s) > -{ > - /* > - * For each accounted object there is an extra space which is used > - * to store obj_cgroup membership. Charge it too. > - */ > - return s->size + sizeof(struct obj_cgroup *); > -} > - > -/* > - * Returns false if the allocation should fail. > - */ > -static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, > - struct list_lru *lru, > - struct obj_cgroup **objcgp, > - size_t objects, gfp_t flags) > -{ > - struct obj_cgroup *objcg; > - > - if (!memcg_kmem_online()) > - return true; > - > - if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) > - return true; > - > - objcg = get_obj_cgroup_from_current(); > - if (!objcg) > - return true; > - > - if (lru) { > - int ret; > - struct mem_cgroup *memcg; > - > - memcg = get_mem_cgroup_from_objcg(objcg); > - ret = memcg_list_lru_alloc(memcg, lru, flags); > - css_put(&memcg->css); > - > - if (ret) > - goto out; > - } > - > - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) > - goto out; > - > - *objcgp = objcg; > - return true; > -out: > - obj_cgroup_put(objcg); > - return false; > -} > - > -static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, > - struct obj_cgroup *objcg, > - gfp_t flags, size_t size, > - void **p) > -{ > - struct slab *slab; > - unsigned long off; > - size_t i; > - > - if (!memcg_kmem_online() || !objcg) > - return; > - > - for (i = 0; i < size; i++) { > - if (likely(p[i])) { > - slab = virt_to_slab(p[i]); > - > - if (!slab_objcgs(slab) && > - memcg_alloc_slab_cgroups(slab, s, flags, > - false)) { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - continue; > - } > - > - off = obj_to_index(s, slab, p[i]); > - obj_cgroup_get(objcg); > - slab_objcgs(slab)[off] = objcg; > - mod_objcg_state(objcg, slab_pgdat(slab), > - cache_vmstat_idx(s), obj_full_size(s)); > - } else { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - } > - } > - obj_cgroup_put(objcg); > -} > - > -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > - void **p, int objects) > -{ > - struct obj_cgroup **objcgs; > - int i; > - > - if (!memcg_kmem_online()) > - return; > - > - objcgs = slab_objcgs(slab); > - if (!objcgs) > - return; > - > - for (i = 0; i < objects; i++) { > - struct obj_cgroup *objcg; > - unsigned int off; > - > - off = obj_to_index(s, slab, p[i]); > - objcg = objcgs[off]; > - if (!objcg) > - continue; > - > - objcgs[off] = NULL; > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), > - -obj_full_size(s)); > - obj_cgroup_put(objcg); > - } > -} > - > -#else /* CONFIG_MEMCG_KMEM */ > static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > { > return NULL; > @@ -632,90 +351,12 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > void **p, int objects) > { > } > -#endif /* CONFIG_MEMCG_KMEM */ > - > -#ifndef CONFIG_SLOB > -static inline struct kmem_cache *virt_to_cache(const void *obj) > -{ > - struct slab *slab; > - > - slab = virt_to_slab(obj); > - if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", > - __func__)) > - return NULL; > - return slab->slab_cache; > -} > - > -static __always_inline void account_slab(struct slab *slab, int order, > - struct kmem_cache *s, gfp_t gfp) > -{ > - if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT)) > - memcg_alloc_slab_cgroups(slab, s, gfp, true); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - PAGE_SIZE << order); > -} > - > -static __always_inline void unaccount_slab(struct slab *slab, int order, > - struct kmem_cache *s) > -{ > - if (memcg_kmem_online()) > - memcg_free_slab_cgroups(slab); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - -(PAGE_SIZE << order)); > -} > - > -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) > -{ > - struct kmem_cache *cachep; > - > - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) > - return s; > - > - cachep = virt_to_cache(x); > - if (WARN(cachep && cachep != s, > - "%s: Wrong slab cache. %s but object is from %s\n", > - __func__, s->name, cachep->name)) > - print_tracking(cachep, x); > - return cachep; > -} > - > -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) > { > -#ifndef CONFIG_SLUB > return s->object_size; > - > -#else /* CONFIG_SLUB */ > -# ifdef CONFIG_SLUB_DEBUG > - /* > - * Debugging requires use of the padding between object > - * and whatever may come after it. > - */ > - if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) > - return s->object_size; > -# endif > - if (s->flags & SLAB_KASAN) > - return s->object_size; > - /* > - * If we have the need to store the freelist pointer > - * back there or track user information then we can > - * only use the space before that information. > - */ > - if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) > - return s->inuse; > - /* > - * Else we can use all the padding etc for the allocation > - */ > - return s->size; > -#endif > } > > static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, > @@ -777,77 +418,18 @@ 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. > - */ > -struct kmem_cache_node { > -#ifdef CONFIG_SLAB > - raw_spinlock_t list_lock; > - struct list_head slabs_partial; /* partial list first, better asm code */ > - struct list_head slabs_full; > - struct list_head slabs_free; > - unsigned long total_slabs; /* length of all slab lists */ > - unsigned long free_slabs; /* length of free slab list only */ > - unsigned long free_objects; > - unsigned int free_limit; > - unsigned int colour_next; /* Per-node cache coloring */ > - struct array_cache *shared; /* shared per node */ > - struct alien_cache **alien; /* on other nodes */ > - unsigned long next_reap; /* updated without locking */ > - int free_touched; /* updated without locking */ > -#endif > - > -#ifdef CONFIG_SLUB > - spinlock_t list_lock; > - unsigned long nr_partial; > - struct list_head partial; > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_t nr_slabs; > - atomic_long_t total_objects; > - struct list_head full; > -#endif > -#endif > - > -}; > - > -static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) > -{ > - return s->node[node]; > -} > - > -/* > - * Iterator over all nodes. The body will be executed for each node that has > - * a kmem_cache_node structure allocated (which is true for all online nodes) > - */ > -#define for_each_kmem_cache_node(__s, __node, __n) \ > - 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); > -#else > static inline void dump_unreclaimable_slab(void) > { > } > -#endif > > void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp); > -void cache_random_seq_destroy(struct kmem_cache *cachep); > -#else > static inline int cache_random_seq_create(struct kmem_cache *cachep, > unsigned int count, gfp_t gfp) > { > return 0; > } > static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > > static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) > { > @@ -871,11 +453,7 @@ static inline bool slab_want_init_on_free(struct kmem_cache *c) > return false; > } > > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -void debugfs_slab_release(struct kmem_cache *); > -#else > static inline void debugfs_slab_release(struct kmem_cache *s) { } > -#endif > > #ifdef CONFIG_PRINTK > #define KS_ADDRS_COUNT 16 > @@ -903,8 +481,4 @@ void __check_heap_object(const void *ptr, unsigned long n, > } > #endif > > -#ifdef CONFIG_SLUB_DEBUG > -void skip_orig_size_check(struct kmem_cache *s, const void *object); > -#endif > - > #endif /* MM_SLAB_H */ > diff --git a/mm/slab_common.c b/mm/slab_common.c > index bf4e777cfe90..5f6a59e31abd 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -69,11 +69,6 @@ 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); > > @@ -195,15 +190,29 @@ 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; > } > > +struct slab_rcu { > + struct rcu_head head; > + int size; > +}; > + > +int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > +{ > + if (flags & SLAB_TYPESAFE_BY_RCU) { > + /* leave room for rcu footer at the end of object */ > + c->size += sizeof(struct slab_rcu); > + } > + > + /* Actual size allocated */ > + c->size = PAGE_SIZE << get_order(c->size); > + c->flags = flags; > + return 0; > +} > + > static struct kmem_cache *create_cache(const char *name, > unsigned int object_size, unsigned int align, > slab_flags_t flags, unsigned int useroffset, > @@ -285,20 +294,6 @@ kmem_cache_create_usercopy(const char *name, > const char *cache_name; > int err; > > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * If no slub_debug was enabled globally, the static key is not yet > - * enabled by setup_slub_debug(). Enable it if the cache is being > - * created with any of the debugging flags passed explicitly. > - * It's also possible that this is the first cache created with > - * SLAB_STORE_USER and we should init stack_depot for it. > - */ > - if (flags & SLAB_DEBUG_FLAGS) > - static_branch_enable(&slub_debug_enabled); > - if (flags & SLAB_STORE_USER) > - stack_depot_init(); > -#endif > - > mutex_lock(&slab_mutex); > > err = kmem_cache_sanity_check(name, size); > @@ -552,7 +547,8 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * > { > if (__kfence_obj_info(kpp, object, slab)) > return; > - __kmem_obj_info(kpp, object, slab); > + kpp->kp_ptr = object; > + kpp->kp_slab = slab; > } > > /** > @@ -625,462 +621,6 @@ 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, > - unsigned int useroffset, unsigned int usersize) > -{ > - int err; > - unsigned int align = ARCH_KMALLOC_MINALIGN; > - > - s->name = name; > - s->size = s->object_size = size; > - > - /* > - * For power of two sizes, guarantee natural alignment for kmalloc > - * caches, regardless of SL*B debugging options. > - */ > - if (is_power_of_2(size)) > - align = max(align, size); > - s->align = calculate_alignment(flags, align, size); > - > -#ifdef CONFIG_HARDENED_USERCOPY > - s->useroffset = useroffset; > - s->usersize = usersize; > -#endif > - > - err = __kmem_cache_create(s, flags); > - > - if (err) > - panic("Creation of kmalloc slab %s size=%u failed. Reason %d\n", > - name, size, err); > - > - s->refcount = -1; /* Exempt from merging for now */ > -} > - > -struct kmem_cache *__init create_kmalloc_cache(const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - > - if (!s) > - panic("Out of memory when creating slab %s\n", name); > - > - create_boot_cache(s, name, size, flags | SLAB_KMALLOC, useroffset, > - usersize); > - list_add(&s->list, &slab_caches); > - s->refcount = 1; > - return s; > -} > - > -struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1] __ro_after_init = > -{ /* initialization for https://bugs.llvm.org/show_bug.cgi?id=42570 */ }; > -EXPORT_SYMBOL(kmalloc_caches); > - > -/* > - * Conversion table for small slabs sizes / 8 to the index in the > - * kmalloc array. This is necessary for slabs < 192 since we have non power > - * of two cache sizes there. The size of larger slabs can be determined using > - * fls. > - */ > -static u8 size_index[24] __ro_after_init = { > - 3, /* 8 */ > - 4, /* 16 */ > - 5, /* 24 */ > - 5, /* 32 */ > - 6, /* 40 */ > - 6, /* 48 */ > - 6, /* 56 */ > - 6, /* 64 */ > - 1, /* 72 */ > - 1, /* 80 */ > - 1, /* 88 */ > - 1, /* 96 */ > - 7, /* 104 */ > - 7, /* 112 */ > - 7, /* 120 */ > - 7, /* 128 */ > - 2, /* 136 */ > - 2, /* 144 */ > - 2, /* 152 */ > - 2, /* 160 */ > - 2, /* 168 */ > - 2, /* 176 */ > - 2, /* 184 */ > - 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 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)][index]; > -} > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - struct kmem_cache *c; > - > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - /* Above the smaller buckets, size is a multiple of page size. */ > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return PAGE_SIZE << get_order(size); > - > - /* The flags don't matter since size_index is common to all. */ > - c = kmalloc_slab(size, GFP_KERNEL); > - return c ? c->object_size : 0; > -} > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -#ifdef CONFIG_ZONE_DMA > -#define KMALLOC_DMA_NAME(sz) .name[KMALLOC_DMA] = "dma-kmalloc-" #sz, > -#else > -#define KMALLOC_DMA_NAME(sz) > -#endif > - > -#ifdef CONFIG_MEMCG_KMEM > -#define KMALLOC_CGROUP_NAME(sz) .name[KMALLOC_CGROUP] = "kmalloc-cg-" #sz, > -#else > -#define KMALLOC_CGROUP_NAME(sz) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz, > -#else > -#define KMALLOC_RCL_NAME(sz) > -#endif > - > -#define INIT_KMALLOC_INFO(__size, __short_size) \ > -{ \ > - .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ > - KMALLOC_RCL_NAME(__short_size) \ > - KMALLOC_CGROUP_NAME(__short_size) \ > - KMALLOC_DMA_NAME(__short_size) \ > - .size = __size, \ > -} > - > -/* > - * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. > - * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is > - * kmalloc-2M. > - */ > -const struct kmalloc_info_struct kmalloc_info[] __initconst = { > - INIT_KMALLOC_INFO(0, 0), > - INIT_KMALLOC_INFO(96, 96), > - INIT_KMALLOC_INFO(192, 192), > - INIT_KMALLOC_INFO(8, 8), > - INIT_KMALLOC_INFO(16, 16), > - INIT_KMALLOC_INFO(32, 32), > - INIT_KMALLOC_INFO(64, 64), > - INIT_KMALLOC_INFO(128, 128), > - INIT_KMALLOC_INFO(256, 256), > - INIT_KMALLOC_INFO(512, 512), > - INIT_KMALLOC_INFO(1024, 1k), > - INIT_KMALLOC_INFO(2048, 2k), > - INIT_KMALLOC_INFO(4096, 4k), > - INIT_KMALLOC_INFO(8192, 8k), > - INIT_KMALLOC_INFO(16384, 16k), > - INIT_KMALLOC_INFO(32768, 32k), > - INIT_KMALLOC_INFO(65536, 64k), > - INIT_KMALLOC_INFO(131072, 128k), > - INIT_KMALLOC_INFO(262144, 256k), > - INIT_KMALLOC_INFO(524288, 512k), > - INIT_KMALLOC_INFO(1048576, 1M), > - INIT_KMALLOC_INFO(2097152, 2M) > -}; > - > -/* > - * Patch up the size_index table if we have strange large alignment > - * requirements for the kmalloc array. This is only the case for > - * MIPS it seems. The standard arches will not generate any code here. > - * > - * Largest permitted alignment is 256 bytes due to the way we > - * handle the index determination for the smaller caches. > - * > - * Make sure that nothing crazy happens if someone starts tinkering > - * around with ARCH_KMALLOC_MINALIGN > - */ > -void __init setup_kmalloc_cache_index_table(void) > -{ > - unsigned int i; > - > - BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || > - !is_power_of_2(KMALLOC_MIN_SIZE)); > - > - for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) { > - unsigned int elem = size_index_elem(i); > - > - if (elem >= ARRAY_SIZE(size_index)) > - break; > - size_index[elem] = KMALLOC_SHIFT_LOW; > - } > - > - if (KMALLOC_MIN_SIZE >= 64) { > - /* > - * The 96 byte sized cache is not used if the alignment > - * is 64 byte. > - */ > - for (i = 64 + 8; i <= 96; i += 8) > - size_index[size_index_elem(i)] = 7; > - > - } > - > - if (KMALLOC_MIN_SIZE >= 128) { > - /* > - * The 192 byte sized cache is not used if the alignment > - * is 128 byte. Redirect kmalloc to use the 256 byte cache > - * instead. > - */ > - for (i = 128 + 8; i <= 192; i += 8) > - size_index[size_index_elem(i)] = 8; > - } > -} > - > -static void __init > -new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > -{ > - if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { > - flags |= SLAB_RECLAIM_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { > - if (mem_cgroup_kmem_disabled()) { > - kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx]; > - return; > - } > - flags |= SLAB_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_ZONE_DMA) && (type == KMALLOC_DMA)) { > - flags |= SLAB_CACHE_DMA; > - } > - > - kmalloc_caches[type][idx] = create_kmalloc_cache( > - kmalloc_info[idx].name[type], > - kmalloc_info[idx].size, flags, 0, > - kmalloc_info[idx].size); > - > - /* > - * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for > - * KMALLOC_NORMAL caches. > - */ > - if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL)) > - kmalloc_caches[type][idx]->refcount = -1; > -} > - > -/* > - * Create the kmalloc array. Some of the regular kmalloc arrays > - * may already have been created because they were needed to > - * enable allocations for slab creation. > - */ > -void __init create_kmalloc_caches(slab_flags_t flags) > -{ > - int i; > - enum kmalloc_cache_type type; > - > - /* > - * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined > - */ > - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { > - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { > - if (!kmalloc_caches[type][i]) > - new_kmalloc_cache(i, type, flags); > - > - /* > - * Caches that are not of the two-to-the-power-of size. > - * These have to be created immediately after the > - * earlier power of two caches > - */ > - if (KMALLOC_MIN_SIZE <= 32 && i == 6 && > - !kmalloc_caches[type][1]) > - new_kmalloc_cache(1, type, flags); > - if (KMALLOC_MIN_SIZE <= 64 && i == 7 && > - !kmalloc_caches[type][2]) > - new_kmalloc_cache(2, type, flags); > - } > - } > - > - /* Kmalloc array is now usable */ > - 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); > - > - 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. > - * > - * If @object is NULL, no operation is performed. > - * > - * Don't free memory not originally allocated by kmalloc() > - * or you will run into trouble. > - */ > -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 > - * > - * This should only be used internally to query the true size of allocations. > - * It is not meant to be a way to discover the usable size of an allocation > - * after the fact. Instead, use kmalloc_size_roundup(). Using memory beyond > - * the originally requested allocation size may trigger KASAN, UBSAN_BOUNDS, > - * and/or FORTIFY_SOURCE. > - * > - * Return: size of the actual memory used by @object in bytes > - */ > -size_t __ksize(const void *object) > -{ > - struct folio *folio; > - > - if (unlikely(object == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(object); > - > - if (unlikely(!folio_test_slab(folio))) { > - if (WARN_ON(folio_size(folio) <= KMALLOC_MAX_CACHE_SIZE)) > - return 0; > - if (WARN_ON(object != folio_address(folio))) > - return 0; > - return folio_size(folio); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - skip_orig_size_check(folio_slab(folio)->slab_cache, object); > -#endif > - > - 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); > -#endif /* !CONFIG_SLOB */ > - > gfp_t kmalloc_fix_flags(gfp_t flags) > { > gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; > @@ -1144,202 +684,44 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) > } > EXPORT_SYMBOL(kmalloc_large_node); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Randomize a generic freelist */ > -static void freelist_randomize(struct rnd_state *state, unsigned int *list, > - unsigned int count) > -{ > - unsigned int rand; > - unsigned int i; > - > - for (i = 0; i < count; i++) > - list[i] = i; > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(state); > - rand %= (i + 1); > - swap(list[i], list[rand]); > - } > -} > - > -/* Create a random sequence per cache */ > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp) > -{ > - struct rnd_state state; > - > - if (count < 2 || cachep->random_seq) > - return 0; > - > - cachep->random_seq = kcalloc(count, sizeof(unsigned int), gfp); > - if (!cachep->random_seq) > - return -ENOMEM; > - > - /* Get best entropy at this stage of boot */ > - prandom_seed_state(&state, get_random_long()); > - > - freelist_randomize(&state, cachep->random_seq, count); > - return 0; > -} > - > -/* Destroy the per-cache random freelist sequence */ > -void cache_random_seq_destroy(struct kmem_cache *cachep) > -{ > - kfree(cachep->random_seq); > - cachep->random_seq = NULL; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -#ifdef CONFIG_SLAB > -#define SLABINFO_RIGHTS (0600) > -#else > -#define SLABINFO_RIGHTS (0400) > -#endif > - > -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'); > -} > - > -static void *slab_start(struct seq_file *m, loff_t *pos) > -{ > - mutex_lock(&slab_mutex); > - return seq_list_start(&slab_caches, *pos); > -} > - > -static void *slab_next(struct seq_file *m, void *p, loff_t *pos) > -{ > - return seq_list_next(p, &slab_caches, pos); > -} > - > -static void slab_stop(struct seq_file *m, void *p) > -{ > - mutex_unlock(&slab_mutex); > -} > - > -static void cache_show(struct kmem_cache *s, struct seq_file *m) > +static __always_inline void * > +__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > { > - struct slabinfo sinfo; > + void *ret; > > - memset(&sinfo, 0, sizeof(sinfo)); > - get_slabinfo(s, &sinfo); > + gfp &= gfp_allowed_mask; > > - seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", > - s->name, sinfo.active_objs, sinfo.num_objs, s->size, > - sinfo.objects_per_slab, (1 << sinfo.cache_order)); > + might_alloc(gfp); > > - seq_printf(m, " : tunables %4u %4u %4u", > - sinfo.limit, sinfo.batchcount, sinfo.shared); > - seq_printf(m, " : slabdata %6lu %6lu %6lu", > - sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail); > - slabinfo_show_stats(m, s); > - seq_putc(m, '\n'); > -} > + if (unlikely(!size)) > + ret = ZERO_SIZE_PTR; > + else > + ret = __kmalloc_large_node(size, gfp, node); > > -static int slab_show(struct seq_file *m, void *p) > -{ > - struct kmem_cache *s = list_entry(p, struct kmem_cache, list); > + trace_kmalloc(caller, ret, size, PAGE_SIZE << get_order(size), gfp, node); > > - if (p == slab_caches.next) > - print_slabinfo_header(m); > - cache_show(s, m); > - return 0; > + kmemleak_alloc(ret, size, 1, gfp); > + return ret; > } > > -void dump_unreclaimable_slab(void) > +void *__kmalloc(size_t size, gfp_t gfp) > { > - struct kmem_cache *s; > - struct slabinfo sinfo; > - > - /* > - * Here acquiring slab_mutex is risky since we don't prefer to get > - * sleep in oom path. But, without mutex hold, it may introduce a > - * risk of crash. > - * Use mutex_trylock to protect the list traverse, dump nothing > - * without acquiring the mutex. > - */ > - if (!mutex_trylock(&slab_mutex)) { > - pr_warn("excessive unreclaimable slab but cannot dump stats\n"); > - return; > - } > - > - pr_info("Unreclaimable slab info:\n"); > - pr_info("Name Used Total\n"); > - > - list_for_each_entry(s, &slab_caches, list) { > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - continue; > - > - get_slabinfo(s, &sinfo); > - > - if (sinfo.num_objs > 0) > - pr_info("%-17s %10luKB %10luKB\n", s->name, > - (sinfo.active_objs * s->size) / 1024, > - (sinfo.num_objs * s->size) / 1024); > - } > - mutex_unlock(&slab_mutex); > + return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc); > > -/* > - * slabinfo_op - iterator that generates /proc/slabinfo > - * > - * Output layout: > - * cache-name > - * num-active-objs > - * total-objs > - * object size > - * num-active-slabs > - * total-slabs > - * num-pages-per-slab > - * + further values on SMP and with statistics enabled > - */ > -static const struct seq_operations slabinfo_op = { > - .start = slab_start, > - .next = slab_next, > - .stop = slab_stop, > - .show = slab_show, > -}; > - > -static int slabinfo_open(struct inode *inode, struct file *file) > +void *__kmalloc_node(size_t size, gfp_t gfp, int node) > { > - return seq_open(file, &slabinfo_op); > + return __do_kmalloc_node(size, gfp, node, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc_node); > > -static const struct proc_ops slabinfo_proc_ops = { > - .proc_flags = PROC_ENTRY_PERMANENT, > - .proc_open = slabinfo_open, > - .proc_read = seq_read, > - .proc_write = slabinfo_write, > - .proc_lseek = seq_lseek, > - .proc_release = seq_release, > -}; > - > -static int __init slab_proc_init(void) > +void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > + int node, unsigned long caller) > { > - proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops); > - return 0; > + return __do_kmalloc_node(size, gfp, node, caller); > } > -module_init(slab_proc_init); > - > -#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */ > +EXPORT_SYMBOL(__kmalloc_node_track_caller); > > static __always_inline __realloc_size(2) void * > __do_krealloc(const void *p, size_t new_size, gfp_t flags) > @@ -1402,6 +784,27 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) > } > EXPORT_SYMBOL(krealloc); > > +void kfree(const void *block) > +{ > + struct folio *sp; > + unsigned int order; > + > + trace_kfree(_RET_IP_, block); > + > + if (unlikely(ZERO_OR_NULL_PTR(block))) > + return; > + kmemleak_free(block); > + > + sp = virt_to_folio(block); > + BUG_ON(folio_test_slab(sp)); > + order = folio_order(sp); > + > + mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > + -(PAGE_SIZE << order)); > + __free_pages(folio_page(sp, 0), order); > +} > +EXPORT_SYMBOL(kfree); > + > /** > * kfree_sensitive - Clear sensitive information in memory before freeing > * @p: object to free memory of > @@ -1427,6 +830,34 @@ void kfree_sensitive(const void *p) > } > EXPORT_SYMBOL(kfree_sensitive); > > +size_t kmalloc_size_roundup(size_t size) > +{ > + /* Short-circuit the 0 size case. */ > + if (unlikely(size == 0)) > + return 0; > + /* Short-circuit saturated "too-large" case. */ > + if (unlikely(size == SIZE_MAX)) > + return SIZE_MAX; > + > + return PAGE_SIZE << get_order(size); > +} > + > +EXPORT_SYMBOL(kmalloc_size_roundup); > + > +/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > +size_t __ksize(const void *block) > +{ > + struct folio *folio; > + > + BUG_ON(!block); > + if (unlikely(block == ZERO_SIZE_PTR)) > + return 0; > + > + folio = virt_to_folio(block); > + BUG_ON(folio_test_slab(folio)); > + return folio_size(folio); > +} > + > size_t ksize(const void *objp) > { > /* > @@ -1451,6 +882,131 @@ size_t ksize(const void *objp) > } > EXPORT_SYMBOL(ksize); > > +static void *__kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > +{ > + void *b; > + > + flags &= gfp_allowed_mask; > + > + might_alloc(flags); > + > + b = __kmalloc_large_node(c->size, flags, node); > + trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > + > + if (b && c->ctor) { > + WARN_ON_ONCE(flags & __GFP_ZERO); > + c->ctor(b); > + } > + > + kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > + return b; > +} > + > +void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc); > + > + > +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_lru); > + > +void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > +{ > + return __kmem_cache_alloc_node(cachep, gfp, node); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_node); > + > +static void kmem_rcu_free(struct rcu_head *head) > +{ > + struct slab_rcu *slab_rcu = (struct slab_rcu *)head; > + void *b = (void *)slab_rcu - (slab_rcu->size - sizeof(struct slab_rcu)); > + > + kfree(b); > +} > + > +void kmem_cache_free(struct kmem_cache *c, void *b) > +{ > + kmemleak_free_recursive(b, c->flags); > + trace_kmem_cache_free(_RET_IP_, b, c); > + if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > + struct slab_rcu *slab_rcu; > + slab_rcu = b + (c->size - sizeof(struct slab_rcu)); > + slab_rcu->size = c->size; > + call_rcu(&slab_rcu->head, kmem_rcu_free); > + } else { > + kfree(b); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free); > + > +void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + if (s) > + kmem_cache_free(s, p[i]); > + else > + kfree(p[i]); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free_bulk); > + > +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > + void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + void *x = p[i] = kmem_cache_alloc(s, flags); > + > + if (!x) { > + kmem_cache_free_bulk(s, i, p); > + return 0; > + } > + } > + return i; > +} > +EXPORT_SYMBOL(kmem_cache_alloc_bulk); > + > +int __kmem_cache_shutdown(struct kmem_cache *c) > +{ > + /* No way to check for remaining objects */ > + return 0; > +} > + > +void __kmem_cache_release(struct kmem_cache *c) > +{ > +} > + > +int __kmem_cache_shrink(struct kmem_cache *d) > +{ > + return 0; > +} > + > +static struct kmem_cache kmem_cache_boot = { > + .name = "kmem_cache", > + .size = sizeof(struct kmem_cache), > + .flags = SLAB_PANIC, > + .align = ARCH_KMALLOC_MINALIGN, > +}; > + > +void __init kmem_cache_init(void) > +{ > + kmem_cache = &kmem_cache_boot; > + slab_state = UP; > +} > + > +void __init kmem_cache_init_late(void) > +{ > + slab_state = FULL; > +} > + > /* Tracepoints definitions. */ > EXPORT_TRACEPOINT_SYMBOL(kmalloc); > EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc); > diff --git a/mm/slob.c b/mm/slob.c > deleted file mode 100644 > index fe567fcfa3a3..000000000000 > --- a/mm/slob.c > +++ /dev/null > @@ -1,757 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLOB Allocator: Simple List Of Blocks > - * > - * Matt Mackall <mpm@xxxxxxxxxxx> 12/30/03 > - * > - * NUMA support by Paul Mundt, 2007. > - * > - * How SLOB works: > - * > - * The core of SLOB is a traditional K&R style heap allocator, with > - * support for returning aligned objects. The granularity of this > - * allocator is as little as 2 bytes, however typically most architectures > - * will require 4 bytes on 32-bit and 8 bytes on 64-bit. > - * > - * The slob heap is a set of linked list of pages from alloc_pages(), > - * and within each page, there is a singly-linked list of free blocks > - * (slob_t). The heap is grown on demand. To reduce fragmentation, > - * heap pages are segregated into three lists, with objects less than > - * 256 bytes, objects less than 1024 bytes, and all other objects. > - * > - * Allocation from heap involves first searching for a page with > - * sufficient free blocks (using a next-fit-like approach) followed by > - * a first-fit scan of the page. Deallocation inserts objects back > - * into the free list in address order, so this is effectively an > - * address-ordered first fit. > - * > - * Above this is an implementation of kmalloc/kfree. Blocks returned > - * from kmalloc are prepended with a 4-byte header with the kmalloc size. > - * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls > - * alloc_pages() directly, allocating compound pages so the page order > - * does not have to be separately tracked. > - * These objects are detected in kfree() because folio_test_slab() > - * is false for them. > - * > - * SLAB is emulated on top of SLOB by simply calling constructors and > - * destructors for every SLAB allocation. Objects are returned with the > - * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which > - * case the low-level allocator will fragment blocks to create the proper > - * alignment. Again, objects of page-size or greater are allocated by > - * calling alloc_pages(). As SLAB objects know their size, no separate > - * size bookkeeping is necessary and there is essentially no allocation > - * space overhead, and compound pages aren't needed for multi-page > - * allocations. > - * > - * NUMA support in SLOB is fairly simplistic, pushing most of the real > - * logic down to the page allocator, and simply doing the node accounting > - * on the upper levels. In the event that a node id is explicitly > - * provided, __alloc_pages_node() with the specified node id is used > - * instead. The common case (or when the node id isn't explicitly provided) > - * will default to the current node, as per numa_node_id(). > - * > - * Node aware pages are still inserted in to the global freelist, and > - * these are scanned for by matching against the node id encoded in the > - * page flags. As a result, block allocations that can be satisfied from > - * the freelist will only be done so on pages residing on the same node, > - * in order to prevent random node placement. > - */ > - > -#include <linux/kernel.h> > -#include <linux/slab.h> > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/cache.h> > -#include <linux/init.h> > -#include <linux/export.h> > -#include <linux/rcupdate.h> > -#include <linux/list.h> > -#include <linux/kmemleak.h> > - > -#include <trace/events/kmem.h> > - > -#include <linux/atomic.h> > - > -#include "slab.h" > -/* > - * slob_block has a field 'units', which indicates size of block if +ve, > - * or offset of next block if -ve (in SLOB_UNITs). > - * > - * Free blocks of size 1 unit simply contain the offset of the next block. > - * Those with larger size contain their size in the first SLOB_UNIT of > - * memory, and the offset of the next free block in the second SLOB_UNIT. > - */ > -#if PAGE_SIZE <= (32767 * 2) > -typedef s16 slobidx_t; > -#else > -typedef s32 slobidx_t; > -#endif > - > -struct slob_block { > - slobidx_t units; > -}; > -typedef struct slob_block slob_t; > - > -/* > - * All partially free slob pages go on these lists. > - */ > -#define SLOB_BREAK1 256 > -#define SLOB_BREAK2 1024 > -static LIST_HEAD(free_slob_small); > -static LIST_HEAD(free_slob_medium); > -static LIST_HEAD(free_slob_large); > - > -/* > - * slob_page_free: true for pages on free_slob_pages list. > - */ > -static inline int slob_page_free(struct slab *slab) > -{ > - return PageSlobFree(slab_page(slab)); > -} > - > -static void set_slob_page_free(struct slab *slab, struct list_head *list) > -{ > - list_add(&slab->slab_list, list); > - __SetPageSlobFree(slab_page(slab)); > -} > - > -static inline void clear_slob_page_free(struct slab *slab) > -{ > - list_del(&slab->slab_list); > - __ClearPageSlobFree(slab_page(slab)); > -} > - > -#define SLOB_UNIT sizeof(slob_t) > -#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) > - > -/* > - * struct slob_rcu is inserted at the tail of allocated slob blocks, which > - * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free > - * the block using call_rcu. > - */ > -struct slob_rcu { > - struct rcu_head head; > - int size; > -}; > - > -/* > - * slob_lock protects all slob allocator structures. > - */ > -static DEFINE_SPINLOCK(slob_lock); > - > -/* > - * Encode the given size and next info into a free slob block s. > - */ > -static void set_slob(slob_t *s, slobidx_t size, slob_t *next) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t offset = next - base; > - > - if (size > 1) { > - s[0].units = size; > - s[1].units = offset; > - } else > - s[0].units = -offset; > -} > - > -/* > - * Return the size of a slob block. > - */ > -static slobidx_t slob_units(slob_t *s) > -{ > - if (s->units > 0) > - return s->units; > - return 1; > -} > - > -/* > - * Return the next free slob block pointer after this one. > - */ > -static slob_t *slob_next(slob_t *s) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t next; > - > - if (s[0].units < 0) > - next = -s[0].units; > - else > - next = s[1].units; > - return base+next; > -} > - > -/* > - * Returns true if s is the last free block in its page. > - */ > -static int slob_last(slob_t *s) > -{ > - return !((unsigned long)slob_next(s) & ~PAGE_MASK); > -} > - > -static void *slob_new_pages(gfp_t gfp, int order, int node) > -{ > - struct page *page; > - > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE) > - page = __alloc_pages_node(node, gfp, order); > - else > -#endif > - page = alloc_pages(gfp, order); > - > - if (!page) > - return NULL; > - > - mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, > - PAGE_SIZE << order); > - return page_address(page); > -} > - > -static void slob_free_pages(void *b, int order) > -{ > - struct page *sp = virt_to_page(b); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - > - mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(sp, order); > -} > - > -/* > - * slob_page_alloc() - Allocate a slob block within a given slob_page sp. > - * @sp: Page to look in. > - * @size: Size of the allocation. > - * @align: Allocation alignment. > - * @align_offset: Offset in the allocated block that will be aligned. > - * @page_removed_from_list: Return parameter. > - * > - * Tries to find a chunk of memory at least @size bytes big within @page. > - * > - * Return: Pointer to memory if allocated, %NULL otherwise. If the > - * allocation fills up @page then the page is removed from the > - * freelist, in this case @page_removed_from_list will be set to > - * true (set to false otherwise). > - */ > -static void *slob_page_alloc(struct slab *sp, size_t size, int align, > - int align_offset, bool *page_removed_from_list) > -{ > - slob_t *prev, *cur, *aligned = NULL; > - int delta = 0, units = SLOB_UNITS(size); > - > - *page_removed_from_list = false; > - for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { > - slobidx_t avail = slob_units(cur); > - > - /* > - * 'aligned' will hold the address of the slob block so that the > - * address 'aligned'+'align_offset' is aligned according to the > - * 'align' parameter. This is for kmalloc() which prepends the > - * allocated block with its size, so that the block itself is > - * aligned when needed. > - */ > - if (align) { > - aligned = (slob_t *) > - (ALIGN((unsigned long)cur + align_offset, align) > - - align_offset); > - delta = aligned - cur; > - } > - if (avail >= units + delta) { /* room enough? */ > - slob_t *next; > - > - if (delta) { /* need to fragment head to align? */ > - next = slob_next(cur); > - set_slob(aligned, avail - delta, next); > - set_slob(cur, delta, aligned); > - prev = cur; > - cur = aligned; > - avail = slob_units(cur); > - } > - > - next = slob_next(cur); > - if (avail == units) { /* exact fit? unlink. */ > - if (prev) > - set_slob(prev, slob_units(prev), next); > - else > - sp->freelist = next; > - } else { /* fragment */ > - if (prev) > - set_slob(prev, slob_units(prev), cur + units); > - else > - sp->freelist = cur + units; > - set_slob(cur + units, avail - units, next); > - } > - > - sp->units -= units; > - if (!sp->units) { > - clear_slob_page_free(sp); > - *page_removed_from_list = true; > - } > - return cur; > - } > - if (slob_last(cur)) > - return NULL; > - } > -} > - > -/* > - * slob_alloc: entry point into the slob allocator. > - */ > -static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, > - int align_offset) > -{ > - struct folio *folio; > - struct slab *sp; > - struct list_head *slob_list; > - slob_t *b = NULL; > - unsigned long flags; > - bool _unused; > - > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - > - spin_lock_irqsave(&slob_lock, flags); > - /* Iterate through each partially free page, try to find room */ > - list_for_each_entry(sp, slob_list, slab_list) { > - bool page_removed_from_list = false; > -#ifdef CONFIG_NUMA > - /* > - * If there's a node specification, search for a partial > - * page with a matching node id in the freelist. > - */ > - if (node != NUMA_NO_NODE && slab_nid(sp) != node) > - continue; > -#endif > - /* Enough room on this page? */ > - if (sp->units < SLOB_UNITS(size)) > - continue; > - > - b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); > - if (!b) > - continue; > - > - /* > - * If slob_page_alloc() removed sp from the list then we > - * cannot call list functions on sp. If so allocation > - * did not fragment the page anyway so optimisation is > - * unnecessary. > - */ > - if (!page_removed_from_list) { > - /* > - * Improve fragment distribution and reduce our average > - * search time by starting our next search here. (see > - * Knuth vol 1, sec 2.5, pg 449) > - */ > - if (!list_is_first(&sp->slab_list, slob_list)) > - list_rotate_to_front(&sp->slab_list, slob_list); > - } > - break; > - } > - spin_unlock_irqrestore(&slob_lock, flags); > - > - /* Not enough space: must allocate a new page */ > - if (!b) { > - b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); > - if (!b) > - return NULL; > - folio = virt_to_folio(b); > - __folio_set_slab(folio); > - sp = folio_slab(folio); > - > - spin_lock_irqsave(&slob_lock, flags); > - sp->units = SLOB_UNITS(PAGE_SIZE); > - sp->freelist = b; > - INIT_LIST_HEAD(&sp->slab_list); > - set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); > - set_slob_page_free(sp, slob_list); > - b = slob_page_alloc(sp, size, align, align_offset, &_unused); > - BUG_ON(!b); > - spin_unlock_irqrestore(&slob_lock, flags); > - } > - if (unlikely(gfp & __GFP_ZERO)) > - memset(b, 0, size); > - return b; > -} > - > -/* > - * slob_free: entry point into the slob allocator. > - */ > -static void slob_free(void *block, int size) > -{ > - struct slab *sp; > - slob_t *prev, *next, *b = (slob_t *)block; > - slobidx_t units; > - unsigned long flags; > - struct list_head *slob_list; > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - BUG_ON(!size); > - > - sp = virt_to_slab(block); > - units = SLOB_UNITS(size); > - > - spin_lock_irqsave(&slob_lock, flags); > - > - if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { > - /* Go directly to page allocator. Do not pass slob allocator */ > - if (slob_page_free(sp)) > - clear_slob_page_free(sp); > - spin_unlock_irqrestore(&slob_lock, flags); > - __folio_clear_slab(slab_folio(sp)); > - slob_free_pages(b, 0); > - return; > - } > - > - if (!slob_page_free(sp)) { > - /* This slob page is about to become partially free. Easy! */ > - sp->units = units; > - sp->freelist = b; > - set_slob(b, units, > - (void *)((unsigned long)(b + > - SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - set_slob_page_free(sp, slob_list); > - goto out; > - } > - > - /* > - * Otherwise the page is already partially free, so find reinsertion > - * point. > - */ > - sp->units += units; > - > - if (b < (slob_t *)sp->freelist) { > - if (b + units == sp->freelist) { > - units += slob_units(sp->freelist); > - sp->freelist = slob_next(sp->freelist); > - } > - set_slob(b, units, sp->freelist); > - sp->freelist = b; > - } else { > - prev = sp->freelist; > - next = slob_next(prev); > - while (b > next) { > - prev = next; > - next = slob_next(prev); > - } > - > - if (!slob_last(prev) && b + units == next) { > - units += slob_units(next); > - set_slob(b, units, slob_next(next)); > - } else > - set_slob(b, units, next); > - > - if (prev + slob_units(prev) == b) { > - units = slob_units(b) + slob_units(prev); > - set_slob(prev, units, slob_next(b)); > - } else > - set_slob(prev, slob_units(prev), b); > - } > -out: > - spin_unlock_irqrestore(&slob_lock, flags); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > -} > -#endif > - > -/* > - * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. > - */ > - > -static __always_inline void * > -__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > -{ > - unsigned int *m; > - unsigned int minalign; > - void *ret; > - > - minalign = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - gfp &= gfp_allowed_mask; > - > - might_alloc(gfp); > - > - if (size < PAGE_SIZE - minalign) { > - int align = minalign; > - > - /* > - * For power of two sizes, guarantee natural alignment for > - * kmalloc()'d objects. > - */ > - if (is_power_of_2(size)) > - align = max_t(unsigned int, minalign, size); > - > - if (!size) > - return ZERO_SIZE_PTR; > - > - m = slob_alloc(size + minalign, gfp, align, node, minalign); > - > - if (!m) > - return NULL; > - *m = size; > - ret = (void *)m + minalign; > - > - trace_kmalloc(caller, ret, size, size + minalign, gfp, node); > - } else { > - unsigned int order = get_order(size); > - > - if (likely(order)) > - gfp |= __GFP_COMP; > - ret = slob_new_pages(gfp, order, node); > - > - trace_kmalloc(caller, ret, size, PAGE_SIZE << order, gfp, node); > - } > - > - kmemleak_alloc(ret, size, 1, gfp); > - return ret; > -} > - > -void *__kmalloc(size_t size, gfp_t gfp) > -{ > - return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, gfp, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -void kfree(const void *block) > -{ > - struct folio *sp; > - > - trace_kfree(_RET_IP_, block); > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - kmemleak_free(block); > - > - sp = virt_to_folio(block); > - if (folio_test_slab(sp)) { > - unsigned int align = max_t(unsigned int, > - ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - unsigned int *m = (unsigned int *)(block - align); > - > - slob_free(m, *m + align); > - } else { > - unsigned int order = folio_order(sp); > - > - mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(sp, 0), order); > - > - } > -} > -EXPORT_SYMBOL(kfree); > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - > - return ALIGN(size, ARCH_KMALLOC_MINALIGN); > -} > - > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > -size_t __ksize(const void *block) > -{ > - struct folio *folio; > - unsigned int align; > - unsigned int *m; > - > - BUG_ON(!block); > - if (unlikely(block == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(block); > - if (unlikely(!folio_test_slab(folio))) > - return folio_size(folio); > - > - align = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - m = (unsigned int *)(block - align); > - return SLOB_UNITS(*m) * SLOB_UNIT; > -} > - > -int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > -{ > - if (flags & SLAB_TYPESAFE_BY_RCU) { > - /* leave room for rcu footer at the end of object */ > - c->size += sizeof(struct slob_rcu); > - } > - > - /* Actual size allocated */ > - c->size = SLOB_UNITS(c->size) * SLOB_UNIT; > - c->flags = flags; > - return 0; > -} > - > -static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > -{ > - void *b; > - > - flags &= gfp_allowed_mask; > - > - might_alloc(flags); > - > - if (c->size < PAGE_SIZE) { > - b = slob_alloc(c->size, flags, c->align, node, 0); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } else { > - b = slob_new_pages(flags, get_order(c->size), node); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } > - > - if (b && c->ctor) { > - WARN_ON_ONCE(flags & __GFP_ZERO); > - c->ctor(b); > - } > - > - kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > - return b; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmalloc_node(size_t size, gfp_t gfp, int node) > -{ > - return __do_kmalloc_node(size, gfp, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > -{ > - return slob_alloc_node(cachep, gfp, node); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static void __kmem_cache_free(void *b, int size) > -{ > - if (size < PAGE_SIZE) > - slob_free(b, size); > - else > - slob_free_pages(b, get_order(size)); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct slob_rcu *slob_rcu = (struct slob_rcu *)head; > - void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); > - > - __kmem_cache_free(b, slob_rcu->size); > -} > - > -void kmem_cache_free(struct kmem_cache *c, void *b) > -{ > - kmemleak_free_recursive(b, c->flags); > - trace_kmem_cache_free(_RET_IP_, b, c); > - if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > - struct slob_rcu *slob_rcu; > - slob_rcu = b + (c->size - sizeof(struct slob_rcu)); > - slob_rcu->size = c->size; > - call_rcu(&slob_rcu->head, kmem_rcu_free); > - } else { > - __kmem_cache_free(b, c->size); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - if (s) > - kmem_cache_free(s, p[i]); > - else > - kfree(p[i]); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > - void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - void *x = p[i] = kmem_cache_alloc(s, flags); > - > - if (!x) { > - kmem_cache_free_bulk(s, i, p); > - return 0; > - } > - } > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -int __kmem_cache_shutdown(struct kmem_cache *c) > -{ > - /* No way to check for remaining objects */ > - return 0; > -} > - > -void __kmem_cache_release(struct kmem_cache *c) > -{ > -} > - > -int __kmem_cache_shrink(struct kmem_cache *d) > -{ > - return 0; > -} > - > -static struct kmem_cache kmem_cache_boot = { > - .name = "kmem_cache", > - .size = sizeof(struct kmem_cache), > - .flags = SLAB_PANIC, > - .align = ARCH_KMALLOC_MINALIGN, > -}; > - > -void __init kmem_cache_init(void) > -{ > - kmem_cache = &kmem_cache_boot; > - slab_state = UP; > -} > - > -void __init kmem_cache_init_late(void) > -{ > - slab_state = FULL; > -} > diff --git a/mm/slub.c b/mm/slub.c > deleted file mode 100644 > index 39327e98fce3..000000000000 > --- a/mm/slub.c > +++ /dev/null > @@ -1,6506 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLUB: A slab allocator that limits cache line use instead of queuing > - * objects in per cpu and per node lists. > - * > - * The allocator synchronizes using per slab locks or atomic operations > - * and only uses a centralized lock to manage a pool of partial slabs. > - * > - * (C) 2007 SGI, Christoph Lameter > - * (C) 2011 Linux Foundation, Christoph Lameter > - */ > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/module.h> > -#include <linux/bit_spinlock.h> > -#include <linux/interrupt.h> > -#include <linux/swab.h> > -#include <linux/bitops.h> > -#include <linux/slab.h> > -#include "slab.h" > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/kasan.h> > -#include <linux/kmsan.h> > -#include <linux/cpu.h> > -#include <linux/cpuset.h> > -#include <linux/mempolicy.h> > -#include <linux/ctype.h> > -#include <linux/stackdepot.h> > -#include <linux/debugobjects.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/memory.h> > -#include <linux/math64.h> > -#include <linux/fault-inject.h> > -#include <linux/stacktrace.h> > -#include <linux/prefetch.h> > -#include <linux/memcontrol.h> > -#include <linux/random.h> > -#include <kunit/test.h> > -#include <kunit/test-bug.h> > -#include <linux/sort.h> > - > -#include <linux/debugfs.h> > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -/* > - * Lock order: > - * 1. slab_mutex (Global Mutex) > - * 2. node->list_lock (Spinlock) > - * 3. kmem_cache->cpu_slab->lock (Local lock) > - * 4. slab_lock(slab) (Only on some arches) > - * 5. object_map_lock (Only for debugging) > - * > - * slab_mutex > - * > - * The role of the slab_mutex is to protect the list of all the slabs > - * and to synchronize major metadata changes to slab cache structures. > - * Also synchronizes memory hotplug callbacks. > - * > - * slab_lock > - * > - * The slab_lock is a wrapper around the page lock, thus it is a bit > - * spinlock. > - * > - * The slab_lock is only used on arches that do not have the ability > - * to do a cmpxchg_double. It only protects: > - * > - * A. slab->freelist -> List of free objects in a slab > - * B. slab->inuse -> Number of objects in use > - * C. slab->objects -> Number of objects in slab > - * D. slab->frozen -> frozen state > - * > - * Frozen slabs > - * > - * If a slab is frozen then it is exempt from list management. It is not > - * on any list except per cpu partial list. The processor that froze the > - * slab is the one who can perform list operations on the slab. Other > - * processors may put objects onto the freelist but the processor that > - * froze the slab is the only one that can retrieve the objects from the > - * slab's freelist. > - * > - * list_lock > - * > - * The list_lock protects the partial and full list on each node and > - * the partial slab counter. If taken then no new slabs may be added or > - * removed from the lists nor make the number of partial slabs be modified. > - * (Note that the total number of slabs is an atomic value that may be > - * modified without taking the list lock). > - * > - * The list_lock is a centralized lock and thus we avoid taking it as > - * much as possible. As long as SLUB does not have to handle partial > - * slabs, operations can continue without any centralized lock. F.e. > - * allocating a long series of objects that fill up slabs does not require > - * the list lock. > - * > - * For debug caches, all allocations are forced to go through a list_lock > - * protected region to serialize against concurrent validation. > - * > - * cpu_slab->lock local lock > - * > - * This locks protect slowpath manipulation of all kmem_cache_cpu fields > - * except the stat counters. This is a percpu structure manipulated only by > - * the local cpu, so the lock protects against being preempted or interrupted > - * by an irq. Fast path operations rely on lockless operations instead. > - * > - * On PREEMPT_RT, the local lock neither disables interrupts nor preemption > - * which means the lockless fastpath cannot be used as it might interfere with > - * an in-progress slow path operations. In this case the local lock is always > - * taken but it still utilizes the freelist for the common operations. > - * > - * lockless fastpaths > - * > - * The fast path allocation (slab_alloc_node()) and freeing (do_slab_free()) > - * are fully lockless when satisfied from the percpu slab (and when > - * cmpxchg_double is possible to use, otherwise slab_lock is taken). > - * They also don't disable preemption or migration or irqs. They rely on > - * the transaction id (tid) field to detect being preempted or moved to > - * another cpu. > - * > - * irq, preemption, migration considerations > - * > - * Interrupts are disabled as part of list_lock or local_lock operations, or > - * around the slab_lock operation, in order to make the slab allocator safe > - * to use in the context of an irq. > - * > - * In addition, preemption (or migration on PREEMPT_RT) is disabled in the > - * allocation slowpath, bulk allocation, and put_cpu_partial(), so that the > - * local cpu doesn't change in the process and e.g. the kmem_cache_cpu pointer > - * doesn't have to be revalidated in each section protected by the local lock. > - * > - * SLUB assigns one slab for allocation to each processor. > - * Allocations only occur from these slabs called cpu slabs. > - * > - * Slabs with free elements are kept on a partial list and during regular > - * operations no list for full slabs is used. If an object in a full slab is > - * freed then the slab will show up again on the partial lists. > - * We track full slabs for debugging purposes though because otherwise we > - * cannot scan all objects. > - * > - * Slabs are freed when they become empty. Teardown and setup is > - * minimal so we rely on the page allocators per cpu caches for > - * fast frees and allocs. > - * > - * slab->frozen The slab is frozen and exempt from list processing. > - * This means that the slab is dedicated to a purpose > - * such as satisfying allocations for a specific > - * processor. Objects may be freed in the slab while > - * it is frozen but slab_free will then skip the usual > - * list operations. It is up to the processor holding > - * the slab to integrate the slab into the slab lists > - * when the slab is no longer needed. > - * > - * One use of this flag is to mark slabs that are > - * used for allocations. Then such a slab becomes a cpu > - * slab. The cpu slab may be equipped with an additional > - * freelist that allows lockless access to > - * free objects in addition to the regular freelist > - * that requires the slab lock. > - * > - * SLAB_DEBUG_FLAGS Slab requires special handling due to debug > - * options set. This moves slab handling out of > - * the fast path and disables lockless freelists. > - */ > - > -/* > - * We could simply use migrate_disable()/enable() but as long as it's a > - * function call even on !PREEMPT_RT, use inline preempt_disable() there. > - */ > -#ifndef CONFIG_PREEMPT_RT > -#define slub_get_cpu_ptr(var) get_cpu_ptr(var) > -#define slub_put_cpu_ptr(var) put_cpu_ptr(var) > -#define USE_LOCKLESS_FAST_PATH() (true) > -#else > -#define slub_get_cpu_ptr(var) \ > -({ \ > - migrate_disable(); \ > - this_cpu_ptr(var); \ > -}) > -#define slub_put_cpu_ptr(var) \ > -do { \ > - (void)(var); \ > - migrate_enable(); \ > -} while (0) > -#define USE_LOCKLESS_FAST_PATH() (false) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define __fastpath_inline __always_inline > -#else > -#define __fastpath_inline > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DEFINE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DEFINE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* Structure holding parameters for get_partial() call chain */ > -struct partial_context { > - struct slab **slab; > - gfp_t flags; > - unsigned int orig_size; > -}; > - > -static inline bool kmem_cache_debug(struct kmem_cache *s) > -{ > - return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); > -} > - > -static inline bool slub_debug_orig_size(struct kmem_cache *s) > -{ > - return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && > - (s->flags & SLAB_KMALLOC)); > -} > - > -void *fixup_red_left(struct kmem_cache *s, void *p) > -{ > - if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) > - p += s->red_left_pad; > - > - return p; > -} > - > -static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - return !kmem_cache_debug(s); > -#else > - return false; > -#endif > -} > - > -/* > - * Issues still to be resolved: > - * > - * - Support PAGE_ALLOC_DEBUG. Should be easy to do. > - * > - * - Variable sizing of the per node arrays > - */ > - > -/* Enable to log cmpxchg failures */ > -#undef SLUB_DEBUG_CMPXCHG > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Minimum number of partial slabs. These will be left on the partial > - * lists even if they are empty. kmem_cache_shrink may reclaim them. > - */ > -#define MIN_PARTIAL 5 > - > -/* > - * Maximum number of desirable partial slabs. > - * The existence of more partial slabs makes kmem_cache_shrink > - * sort the partial list by the number of objects in use. > - */ > -#define MAX_PARTIAL 10 > -#else > -#define MIN_PARTIAL 0 > -#define MAX_PARTIAL 0 > -#endif > - > -#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ > - SLAB_POISON | SLAB_STORE_USER) > - > -/* > - * These debug flags cannot use CMPXCHG because there might be consistency > - * issues when checking or reading debug information > - */ > -#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ > - SLAB_TRACE) > - > - > -/* > - * Debugging flags that require metadata to be stored in the slab. These get > - * disabled when slub_debug=O is used and a cache's min order increases with > - * metadata. > - */ > -#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > - > -#define OO_SHIFT 16 > -#define OO_MASK ((1 << OO_SHIFT) - 1) > -#define MAX_OBJS_PER_PAGE 32767 /* since slab.objects is u15 */ > - > -/* Internal SLUB flags */ > -/* Poison object */ > -#define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) > -/* Use cmpxchg_double */ > -#define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) > - > -/* > - * Tracking user of a slab. > - */ > -#define TRACK_ADDRS_COUNT 16 > -struct track { > - unsigned long addr; /* Called from address */ > -#ifdef CONFIG_STACKDEPOT > - depot_stack_handle_t handle; > -#endif > - int cpu; /* Was running on cpu */ > - int pid; /* Pid context */ > - unsigned long when; /* When did the operation occur */ > -}; > - > -enum track_item { TRACK_ALLOC, TRACK_FREE }; > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int sysfs_slab_add(struct kmem_cache *); > -static int sysfs_slab_alias(struct kmem_cache *, const char *); > -#else > -static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } > -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) > - { return 0; } > -#endif > - > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -static void debugfs_slab_add(struct kmem_cache *); > -#else > -static inline void debugfs_slab_add(struct kmem_cache *s) { } > -#endif > - > -static inline void stat(const struct kmem_cache *s, enum stat_item si) > -{ > -#ifdef CONFIG_SLUB_STATS > - /* > - * The rmw is racy on a preemptible kernel but this is acceptable, so > - * avoid this_cpu_add()'s irq-disable overhead. > - */ > - raw_cpu_inc(s->cpu_slab->stat[si]); > -#endif > -} > - > -/* > - * Tracks for which NUMA nodes we have kmem_cache_nodes allocated. > - * Corresponds to node_state[N_NORMAL_MEMORY], but can temporarily > - * differ during memory hotplug/hotremove operations. > - * Protected by slab_mutex. > - */ > -static nodemask_t slab_nodes; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Workqueue used for flush_cpu_slab(). > - */ > -static struct workqueue_struct *flushwq; > -#endif > - > -/******************************************************************** > - * Core slab cache functions > - *******************************************************************/ > - > -/* > - * Returns freelist pointer (ptr). With hardening, this is obfuscated > - * with an XOR of the address where the pointer is held and a per-cache > - * random number. > - */ > -static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, > - unsigned long ptr_addr) > -{ > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - /* > - * When CONFIG_KASAN_SW/HW_TAGS is enabled, ptr_addr might be tagged. > - * Normally, this doesn't cause any issues, as both set_freepointer() > - * and get_freepointer() are called with a pointer with the same tag. > - * However, there are some issues with CONFIG_SLUB_DEBUG code. For > - * example, when __free_slub() iterates over objects in a cache, it > - * passes untagged pointers to check_object(). check_object() in turns > - * calls get_freepointer() with an untagged pointer, which causes the > - * freepointer to be restored incorrectly. > - */ > - return (void *)((unsigned long)ptr ^ s->random ^ > - swab((unsigned long)kasan_reset_tag((void *)ptr_addr))); > -#else > - return ptr; > -#endif > -} > - > -/* Returns the freelist pointer recorded at location ptr_addr. */ > -static inline void *freelist_dereference(const struct kmem_cache *s, > - void *ptr_addr) > -{ > - return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), > - (unsigned long)ptr_addr); > -} > - > -static inline void *get_freepointer(struct kmem_cache *s, void *object) > -{ > - object = kasan_reset_tag(object); > - return freelist_dereference(s, object + s->offset); > -} > - > -#ifndef CONFIG_SLUB_TINY > -static void prefetch_freepointer(const struct kmem_cache *s, void *object) > -{ > - prefetchw(object + s->offset); > -} > -#endif > - > -/* > - * When running under KMSAN, get_freepointer_safe() may return an uninitialized > - * pointer value in the case the current thread loses the race for the next > - * memory chunk in the freelist. In that case this_cpu_cmpxchg_double() in > - * slab_alloc_node() will fail, so the uninitialized value won't be used, but > - * KMSAN will still check all arguments of cmpxchg because of imperfect > - * handling of inline assembly. > - * To work around this problem, we apply __no_kmsan_checks to ensure that > - * get_freepointer_safe() returns initialized memory. > - */ > -__no_kmsan_checks > -static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) > -{ > - unsigned long freepointer_addr; > - void *p; > - > - if (!debug_pagealloc_enabled_static()) > - return get_freepointer(s, object); > - > - object = kasan_reset_tag(object); > - freepointer_addr = (unsigned long)object + s->offset; > - copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); > - return freelist_ptr(s, p, freepointer_addr); > -} > - > -static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) > -{ > - unsigned long freeptr_addr = (unsigned long)object + s->offset; > - > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - BUG_ON(object == fp); /* naive detection of double free or corruption */ > -#endif > - > - freeptr_addr = (unsigned long)kasan_reset_tag((void *)freeptr_addr); > - *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); > -} > - > -/* Loop over all objects in a slab */ > -#define for_each_object(__p, __s, __addr, __objects) \ > - for (__p = fixup_red_left(__s, __addr); \ > - __p < (__addr) + (__objects) * (__s)->size; \ > - __p += (__s)->size) > - > -static inline unsigned int order_objects(unsigned int order, unsigned int size) > -{ > - return ((unsigned int)PAGE_SIZE << order) / size; > -} > - > -static inline struct kmem_cache_order_objects oo_make(unsigned int order, > - unsigned int size) > -{ > - struct kmem_cache_order_objects x = { > - (order << OO_SHIFT) + order_objects(order, size) > - }; > - > - return x; > -} > - > -static inline unsigned int oo_order(struct kmem_cache_order_objects x) > -{ > - return x.x >> OO_SHIFT; > -} > - > -static inline unsigned int oo_objects(struct kmem_cache_order_objects x) > -{ > - return x.x & OO_MASK; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > - unsigned int nr_slabs; > - > - s->cpu_partial = nr_objects; > - > - /* > - * We take the number of objects but actually limit the number of > - * slabs on the per cpu partial list, in order to limit excessive > - * growth of the list. For simplicity we assume that the slabs will > - * be half-full. > - */ > - nr_slabs = DIV_ROUND_UP(nr_objects * 2, oo_objects(s->oo)); > - s->cpu_partial_slabs = nr_slabs; > -} > -#else > -static inline void > -slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > -} > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -/* > - * Per slab locking using the pagelock > - */ > -static __always_inline void slab_lock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - bit_spin_lock(PG_locked, &page->flags); > -} > - > -static __always_inline void slab_unlock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - __bit_spin_unlock(PG_locked, &page->flags); > -} > - > -/* > - * Interrupts must be disabled (for the fallback code to work right), typically > - * by an _irqsave() lock variant. On PREEMPT_RT the preempt_disable(), which is > - * part of bit_spin_lock(), is sufficient because the policy is not to allow any > - * allocation/ free operation in hardirq context. Therefore nothing can > - * interrupt the operation. > - */ > -static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > - if (USE_LOCKLESS_FAST_PATH()) > - lockdep_assert_irqs_disabled(); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - return true; > - } > - slab_unlock(slab); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - unsigned long flags; > - > - local_irq_save(flags); > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - local_irq_restore(flags); > - return true; > - } > - slab_unlock(slab); > - local_irq_restore(flags); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; > -static DEFINE_SPINLOCK(object_map_lock); > - > -static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, > - struct slab *slab) > -{ > - void *addr = slab_address(slab); > - void *p; > - > - bitmap_zero(obj_map, slab->objects); > - > - for (p = slab->freelist; p; p = get_freepointer(s, p)) > - set_bit(__obj_to_index(s, addr, p), obj_map); > -} > - > -#if IS_ENABLED(CONFIG_KUNIT) > -static bool slab_add_kunit_errors(void) > -{ > - struct kunit_resource *resource; > - > - if (!kunit_get_current_test()) > - return false; > - > - resource = kunit_find_named_resource(current->kunit_test, "slab_errors"); > - if (!resource) > - return false; > - > - (*(int *)resource->data)++; > - kunit_put_resource(resource); > - return true; > -} > -#else > -static inline bool slab_add_kunit_errors(void) { return false; } > -#endif > - > -static inline unsigned int size_from_object(struct kmem_cache *s) > -{ > - if (s->flags & SLAB_RED_ZONE) > - return s->size - s->red_left_pad; > - > - return s->size; > -} > - > -static inline void *restore_red_left(struct kmem_cache *s, void *p) > -{ > - if (s->flags & SLAB_RED_ZONE) > - p -= s->red_left_pad; > - > - return p; > -} > - > -/* > - * Debug settings: > - */ > -#if defined(CONFIG_SLUB_DEBUG_ON) > -static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; > -#else > -static slab_flags_t slub_debug; > -#endif > - > -static char *slub_debug_string; > -static int disable_higher_order_debug; > - > -/* > - * slub is about to manipulate internal object metadata. This memory lies > - * outside the range of the allocated object, so accessing it would normally > - * be reported by kasan as a bounds error. metadata_access_enable() is used > - * to tell kasan that these accesses are OK. > - */ > -static inline void metadata_access_enable(void) > -{ > - kasan_disable_current(); > -} > - > -static inline void metadata_access_disable(void) > -{ > - kasan_enable_current(); > -} > - > -/* > - * Object debugging > - */ > - > -/* Verify that a pointer has an address that is valid within a slab page */ > -static inline int check_valid_pointer(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - void *base; > - > - if (!object) > - return 1; > - > - base = slab_address(slab); > - object = kasan_reset_tag(object); > - object = restore_red_left(s, object); > - if (object < base || object >= base + slab->objects * s->size || > - (object - base) % s->size) { > - return 0; > - } > - > - return 1; > -} > - > -static void print_section(char *level, char *text, u8 *addr, > - unsigned int length) > -{ > - metadata_access_enable(); > - print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, > - 16, 1, kasan_reset_tag((void *)addr), length, 1); > - metadata_access_disable(); > -} > - > -/* > - * See comment in calculate_sizes(). > - */ > -static inline bool freeptr_outside_object(struct kmem_cache *s) > -{ > - return s->offset >= s->inuse; > -} > - > -/* > - * Return offset of the end of info block which is inuse + free pointer if > - * not overlapping with object. > - */ > -static inline unsigned int get_info_end(struct kmem_cache *s) > -{ > - if (freeptr_outside_object(s)) > - return s->inuse + sizeof(void *); > - else > - return s->inuse; > -} > - > -static struct track *get_track(struct kmem_cache *s, void *object, > - enum track_item alloc) > -{ > - struct track *p; > - > - p = object + get_info_end(s); > - > - return kasan_reset_tag(p + alloc); > -} > - > -#ifdef CONFIG_STACKDEPOT > -static noinline depot_stack_handle_t set_track_prepare(void) > -{ > - depot_stack_handle_t handle; > - unsigned long entries[TRACK_ADDRS_COUNT]; > - unsigned int nr_entries; > - > - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); > - handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); > - > - return handle; > -} > -#else > -static inline depot_stack_handle_t set_track_prepare(void) > -{ > - return 0; > -} > -#endif > - > -static void set_track_update(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr, > - depot_stack_handle_t handle) > -{ > - struct track *p = get_track(s, object, alloc); > - > -#ifdef CONFIG_STACKDEPOT > - p->handle = handle; > -#endif > - p->addr = addr; > - p->cpu = smp_processor_id(); > - p->pid = current->pid; > - p->when = jiffies; > -} > - > -static __always_inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) > -{ > - depot_stack_handle_t handle = set_track_prepare(); > - > - set_track_update(s, object, alloc, addr, handle); > -} > - > -static void init_tracking(struct kmem_cache *s, void *object) > -{ > - struct track *p; > - > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - p = get_track(s, object, TRACK_ALLOC); > - memset(p, 0, 2*sizeof(struct track)); > -} > - > -static void print_track(const char *s, struct track *t, unsigned long pr_time) > -{ > - depot_stack_handle_t handle __maybe_unused; > - > - if (!t->addr) > - return; > - > - pr_err("%s in %pS age=%lu cpu=%u pid=%d\n", > - s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(t->handle); > - if (handle) > - stack_depot_print(handle); > - else > - pr_err("object allocation/free stack trace missing\n"); > -#endif > -} > - > -void print_tracking(struct kmem_cache *s, void *object) > -{ > - unsigned long pr_time = jiffies; > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); > - print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); > -} > - > -static void print_slab_info(const struct slab *slab) > -{ > - struct folio *folio = (struct folio *)slab_folio(slab); > - > - pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n", > - slab, slab->objects, slab->inuse, slab->freelist, > - folio_flags(folio, 0)); > -} > - > -/* > - * kmalloc caches has fixed sizes (mostly power of 2), and kmalloc() API > - * family will round up the real request size to these fixed ones, so > - * there could be an extra area than what is requested. Save the original > - * request size in the meta data area, for better debug and sanity check. > - */ > -static inline void set_orig_size(struct kmem_cache *s, > - void *object, unsigned int orig_size) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return; > - > -#ifdef CONFIG_KASAN_GENERIC > - /* > - * KASAN could save its free meta data in object's data area at > - * offset 0, if the size is larger than 'orig_size', it will > - * overlap the data redzone in [orig_size+1, object_size], and > - * the check should be skipped. > - */ > - if (kasan_metadata_size(s, true) > orig_size) > - orig_size = s->object_size; > -#endif > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - *(unsigned int *)p = orig_size; > -} > - > -static inline unsigned int get_orig_size(struct kmem_cache *s, void *object) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return s->object_size; > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - return *(unsigned int *)p; > -} > - > -void skip_orig_size_check(struct kmem_cache *s, const void *object) > -{ > - set_orig_size(s, (void *)object, s->object_size); > -} > - > -static void slab_bug(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("=============================================================================\n"); > - pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); > - pr_err("-----------------------------------------------------------------------------\n\n"); > - va_end(args); > -} > - > -__printf(2, 3) > -static void slab_fix(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("FIX %s: %pV\n", s->name, &vaf); > - va_end(args); > -} > - > -static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned int off; /* Offset of last byte */ > - u8 *addr = slab_address(slab); > - > - print_tracking(s, p); > - > - print_slab_info(slab); > - > - pr_err("Object 0x%p @offset=%tu fp=0x%p\n\n", > - p, p - addr, get_freepointer(s, p)); > - > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, > - s->red_left_pad); > - else if (p > addr + 16) > - print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); > - > - print_section(KERN_ERR, "Object ", p, > - min_t(unsigned int, s->object_size, PAGE_SIZE)); > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p + s->object_size, > - s->inuse - s->object_size); > - > - off = get_info_end(s); > - > - if (s->flags & SLAB_STORE_USER) > - off += 2 * sizeof(struct track); > - > - if (slub_debug_orig_size(s)) > - off += sizeof(unsigned int); > - > - off += kasan_metadata_size(s, false); > - > - if (off != size_from_object(s)) > - /* Beginning of the filler is the free pointer */ > - print_section(KERN_ERR, "Padding ", p + off, > - size_from_object(s) - off); > - > - dump_stack(); > -} > - > -static void object_err(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *reason) > -{ > - if (slab_add_kunit_errors()) > - return; > - > - slab_bug(s, "%s", reason); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - if ((s->flags & SLAB_CONSISTENCY_CHECKS) && > - !check_valid_pointer(s, slab, nextfree) && freelist) { > - object_err(s, slab, *freelist, "Freechain corrupt"); > - *freelist = NULL; > - slab_fix(s, "Isolate corrupted freechain"); > - return true; > - } > - > - return false; > -} > - > -static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab, > - const char *fmt, ...) > -{ > - va_list args; > - char buf[100]; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vsnprintf(buf, sizeof(buf), fmt, args); > - va_end(args); > - slab_bug(s, "%s", buf); > - print_slab_info(slab); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static void init_object(struct kmem_cache *s, void *object, u8 val) > -{ > - u8 *p = kasan_reset_tag(object); > - unsigned int poison_size = s->object_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - memset(p - s->red_left_pad, val, s->red_left_pad); > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - /* > - * Redzone the extra allocated space by kmalloc than > - * requested, and the poison size will be limited to > - * the original request size accordingly. > - */ > - poison_size = get_orig_size(s, object); > - } > - } > - > - if (s->flags & __OBJECT_POISON) { > - memset(p, POISON_FREE, poison_size - 1); > - p[poison_size - 1] = POISON_END; > - } > - > - if (s->flags & SLAB_RED_ZONE) > - memset(p + poison_size, val, s->inuse - poison_size); > -} > - > -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, > - void *from, void *to) > -{ > - slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); > - memset(from, data, to - from); > -} > - > -static int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *what, > - u8 *start, unsigned int value, unsigned int bytes) > -{ > - u8 *fault; > - u8 *end; > - u8 *addr = slab_address(slab); > - > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(start), value, bytes); > - metadata_access_disable(); > - if (!fault) > - return 1; > - > - end = start + bytes; > - while (end > fault && end[-1] == value) > - end--; > - > - if (slab_add_kunit_errors()) > - goto skip_bug_print; > - > - slab_bug(s, "%s overwritten", what); > - pr_err("0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n", > - fault, end - 1, fault - addr, > - fault[0], value); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > - > -skip_bug_print: > - restore_bytes(s, what, value, fault, end); > - return 0; > -} > - > -/* > - * Object layout: > - * > - * object address > - * Bytes of the object to be managed. > - * If the freepointer may overlay the object then the free > - * pointer is at the middle of the object. > - * > - * Poisoning uses 0x6b (POISON_FREE) and the last byte is > - * 0xa5 (POISON_END) > - * > - * object + s->object_size > - * Padding to reach word boundary. This is also used for Redzoning. > - * Padding is extended by another word if Redzoning is enabled and > - * object_size == inuse. > - * > - * We fill with 0xbb (RED_INACTIVE) for inactive objects and with > - * 0xcc (RED_ACTIVE) for objects in use. > - * > - * object + s->inuse > - * Meta data starts here. > - * > - * A. Free pointer (if we cannot overwrite object on free) > - * B. Tracking data for SLAB_STORE_USER > - * C. Original request size for kmalloc object (SLAB_STORE_USER enabled) > - * D. Padding to reach required alignment boundary or at minimum > - * one word if debugging is on to be able to detect writes > - * before the word boundary. > - * > - * Padding is done using 0x5a (POISON_INUSE) > - * > - * object + s->size > - * Nothing is used beyond s->size. > - * > - * If slabcaches are merged then the object_size and inuse boundaries are mostly > - * ignored. And therefore no slab options that rely on these boundaries > - * may be used with merged slabcaches. > - */ > - > -static int check_pad_bytes(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned long off = get_info_end(s); /* The end of info */ > - > - if (s->flags & SLAB_STORE_USER) { > - /* We also have user information there */ > - off += 2 * sizeof(struct track); > - > - if (s->flags & SLAB_KMALLOC) > - off += sizeof(unsigned int); > - } > - > - off += kasan_metadata_size(s, false); > - > - if (size_from_object(s) == off) > - return 1; > - > - return check_bytes_and_report(s, slab, p, "Object padding", > - p + off, POISON_INUSE, size_from_object(s) - off); > -} > - > -/* Check the pad bytes at the end of a slab page */ > -static void slab_pad_check(struct kmem_cache *s, struct slab *slab) > -{ > - u8 *start; > - u8 *fault; > - u8 *end; > - u8 *pad; > - int length; > - int remainder; > - > - if (!(s->flags & SLAB_POISON)) > - return; > - > - start = slab_address(slab); > - length = slab_size(slab); > - end = start + length; > - remainder = length % s->size; > - if (!remainder) > - return; > - > - pad = end - remainder; > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(pad), POISON_INUSE, remainder); > - metadata_access_disable(); > - if (!fault) > - return; > - while (end > fault && end[-1] == POISON_INUSE) > - end--; > - > - slab_err(s, slab, "Padding overwritten. 0x%p-0x%p @offset=%tu", > - fault, end - 1, fault - start); > - print_section(KERN_ERR, "Padding ", pad, remainder); > - > - restore_bytes(s, "slab padding", POISON_INUSE, fault, end); > -} > - > -static int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) > -{ > - u8 *p = object; > - u8 *endobject = object + s->object_size; > - unsigned int orig_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - if (!check_bytes_and_report(s, slab, object, "Left Redzone", > - object - s->red_left_pad, val, s->red_left_pad)) > - return 0; > - > - if (!check_bytes_and_report(s, slab, object, "Right Redzone", > - endobject, val, s->inuse - s->object_size)) > - return 0; > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - orig_size = get_orig_size(s, object); > - > - if (s->object_size > orig_size && > - !check_bytes_and_report(s, slab, object, > - "kmalloc Redzone", p + orig_size, > - val, s->object_size - orig_size)) { > - return 0; > - } > - } > - } else { > - if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { > - check_bytes_and_report(s, slab, p, "Alignment padding", > - endobject, POISON_INUSE, > - s->inuse - s->object_size); > - } > - } > - > - if (s->flags & SLAB_POISON) { > - if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && > - (!check_bytes_and_report(s, slab, p, "Poison", p, > - POISON_FREE, s->object_size - 1) || > - !check_bytes_and_report(s, slab, p, "End Poison", > - p + s->object_size - 1, POISON_END, 1))) > - return 0; > - /* > - * check_pad_bytes cleans up on its own. > - */ > - check_pad_bytes(s, slab, p); > - } > - > - if (!freeptr_outside_object(s) && val == SLUB_RED_ACTIVE) > - /* > - * Object and freepointer overlap. Cannot check > - * freepointer while object is allocated. > - */ > - return 1; > - > - /* Check free pointer validity */ > - if (!check_valid_pointer(s, slab, get_freepointer(s, p))) { > - object_err(s, slab, p, "Freepointer corrupt"); > - /* > - * No choice but to zap it and thus lose the remainder > - * of the free objects in this slab. May cause > - * another error because the object count is now wrong. > - */ > - set_freepointer(s, p, NULL); > - return 0; > - } > - return 1; > -} > - > -static int check_slab(struct kmem_cache *s, struct slab *slab) > -{ > - int maxobj; > - > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Not a valid slab page"); > - return 0; > - } > - > - maxobj = order_objects(slab_order(slab), s->size); > - if (slab->objects > maxobj) { > - slab_err(s, slab, "objects %u > max %u", > - slab->objects, maxobj); > - return 0; > - } > - if (slab->inuse > slab->objects) { > - slab_err(s, slab, "inuse %u > max %u", > - slab->inuse, slab->objects); > - return 0; > - } > - /* Slab_pad_check fixes things up after itself */ > - slab_pad_check(s, slab); > - return 1; > -} > - > -/* > - * Determine if a certain object in a slab is on the freelist. Must hold the > - * slab lock to guarantee that the chains are in a consistent state. > - */ > -static int on_freelist(struct kmem_cache *s, struct slab *slab, void *search) > -{ > - int nr = 0; > - void *fp; > - void *object = NULL; > - int max_objects; > - > - fp = slab->freelist; > - while (fp && nr <= slab->objects) { > - if (fp == search) > - return 1; > - if (!check_valid_pointer(s, slab, fp)) { > - if (object) { > - object_err(s, slab, object, > - "Freechain corrupt"); > - set_freepointer(s, object, NULL); > - } else { > - slab_err(s, slab, "Freepointer corrupt"); > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab_fix(s, "Freelist cleared"); > - return 0; > - } > - break; > - } > - object = fp; > - fp = get_freepointer(s, object); > - nr++; > - } > - > - max_objects = order_objects(slab_order(slab), s->size); > - if (max_objects > MAX_OBJS_PER_PAGE) > - max_objects = MAX_OBJS_PER_PAGE; > - > - if (slab->objects != max_objects) { > - slab_err(s, slab, "Wrong number of objects. Found %d but should be %d", > - slab->objects, max_objects); > - slab->objects = max_objects; > - slab_fix(s, "Number of objects adjusted"); > - } > - if (slab->inuse != slab->objects - nr) { > - slab_err(s, slab, "Wrong object count. Counter is %d but counted were %d", > - slab->inuse, slab->objects - nr); > - slab->inuse = slab->objects - nr; > - slab_fix(s, "Object count adjusted"); > - } > - return search == NULL; > -} > - > -static void trace(struct kmem_cache *s, struct slab *slab, void *object, > - int alloc) > -{ > - if (s->flags & SLAB_TRACE) { > - pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", > - s->name, > - alloc ? "alloc" : "free", > - object, slab->inuse, > - slab->freelist); > - > - if (!alloc) > - print_section(KERN_INFO, "Object ", (void *)object, > - s->object_size); > - > - dump_stack(); > - } > -} > - > -/* > - * Tracking of fully allocated slabs for debugging purposes. > - */ > -static void add_full(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_add(&slab->slab_list, &n->full); > -} > - > -static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > -} > - > -/* Tracking of the number of slabs for debugging purposes */ > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - /* > - * May be called early in order to allocate a slab for the > - * kmem_cache_node structure. Solve the chicken-egg > - * dilemma by deferring the increment of the count during > - * bootstrap (see early_kmem_cache_node_alloc). > - */ > - if (likely(n)) { > - atomic_long_inc(&n->nr_slabs); > - atomic_long_add(objects, &n->total_objects); > - } > -} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - atomic_long_dec(&n->nr_slabs); > - atomic_long_sub(objects, &n->total_objects); > -} > - > -/* Object debug checks for alloc/free paths */ > -static void setup_object_debug(struct kmem_cache *s, void *object) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)) > - return; > - > - init_object(s, object, SLUB_RED_INACTIVE); > - init_tracking(s, object); > -} > - > -static > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_POISON)) > - return; > - > - metadata_access_enable(); > - memset(kasan_reset_tag(addr), POISON_INUSE, slab_size(slab)); > - metadata_access_disable(); > -} > - > -static inline int alloc_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - if (!check_slab(s, slab)) > - return 0; > - > - if (!check_valid_pointer(s, slab, object)) { > - object_err(s, slab, object, "Freelist Pointer check fails"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_INACTIVE)) > - return 0; > - > - return 1; > -} > - > -static noinline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) > -{ > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!alloc_consistency_checks(s, slab, object)) > - goto bad; > - } > - > - /* Success. Perform special debug activities for allocs */ > - trace(s, slab, object, 1); > - set_orig_size(s, object, orig_size); > - init_object(s, object, SLUB_RED_ACTIVE); > - return true; > - > -bad: > - if (folio_test_slab(slab_folio(slab))) { > - /* > - * If this is a slab page then lets do the best we can > - * to avoid issues in the future. Marking all objects > - * as used avoids touching the remaining objects. > - */ > - slab_fix(s, "Marking all objects used"); > - slab->inuse = slab->objects; > - slab->freelist = NULL; > - } > - return false; > -} > - > -static inline int free_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object, unsigned long addr) > -{ > - if (!check_valid_pointer(s, slab, object)) { > - slab_err(s, slab, "Invalid object pointer 0x%p", object); > - return 0; > - } > - > - if (on_freelist(s, slab, object)) { > - object_err(s, slab, object, "Object already free"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_ACTIVE)) > - return 0; > - > - if (unlikely(s != slab->slab_cache)) { > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Attempt to free object(0x%p) outside of slab", > - object); > - } else if (!slab->slab_cache) { > - pr_err("SLUB <none>: no slab for object 0x%p.\n", > - object); > - dump_stack(); > - } else > - object_err(s, slab, object, > - "page slab pointer corrupt."); > - return 0; > - } > - return 1; > -} > - > -/* > - * Parse a block of slub_debug options. Blocks are delimited by ';' > - * > - * @str: start of block > - * @flags: returns parsed flags, or DEBUG_DEFAULT_FLAGS if none specified > - * @slabs: return start of list of slabs, or NULL when there's no list > - * @init: assume this is initial parsing and not per-kmem-create parsing > - * > - * returns the start of next block if there's any, or NULL > - */ > -static char * > -parse_slub_debug_flags(char *str, slab_flags_t *flags, char **slabs, bool init) > -{ > - bool higher_order_disable = false; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (*str == ',') { > - /* > - * No options but restriction on slabs. This means full > - * debugging for slabs matching a pattern. > - */ > - *flags = DEBUG_DEFAULT_FLAGS; > - goto check_slabs; > - } > - *flags = 0; > - > - /* Determine which debug features should be switched on */ > - for (; *str && *str != ',' && *str != ';'; str++) { > - switch (tolower(*str)) { > - case '-': > - *flags = 0; > - break; > - case 'f': > - *flags |= SLAB_CONSISTENCY_CHECKS; > - break; > - case 'z': > - *flags |= SLAB_RED_ZONE; > - break; > - case 'p': > - *flags |= SLAB_POISON; > - break; > - case 'u': > - *flags |= SLAB_STORE_USER; > - break; > - case 't': > - *flags |= SLAB_TRACE; > - break; > - case 'a': > - *flags |= SLAB_FAILSLAB; > - break; > - case 'o': > - /* > - * Avoid enabling debugging on caches if its minimum > - * order would increase as a result. > - */ > - higher_order_disable = true; > - break; > - default: > - if (init) > - pr_err("slub_debug option '%c' unknown. skipped\n", *str); > - } > - } > -check_slabs: > - if (*str == ',') > - *slabs = ++str; > - else > - *slabs = NULL; > - > - /* Skip over the slab list */ > - while (*str && *str != ';') > - str++; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (init && higher_order_disable) > - disable_higher_order_debug = 1; > - > - if (*str) > - return str; > - else > - return NULL; > -} > - > -static int __init setup_slub_debug(char *str) > -{ > - slab_flags_t flags; > - slab_flags_t global_flags; > - char *saved_str; > - char *slab_list; > - bool global_slub_debug_changed = false; > - bool slab_list_specified = false; > - > - global_flags = DEBUG_DEFAULT_FLAGS; > - if (*str++ != '=' || !*str) > - /* > - * No options specified. Switch on full debugging. > - */ > - goto out; > - > - saved_str = str; > - while (str) { > - str = parse_slub_debug_flags(str, &flags, &slab_list, true); > - > - if (!slab_list) { > - global_flags = flags; > - global_slub_debug_changed = true; > - } else { > - slab_list_specified = true; > - if (flags & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - } > - } > - > - /* > - * For backwards compatibility, a single list of flags with list of > - * slabs means debugging is only changed for those slabs, so the global > - * slub_debug should be unchanged (0 or DEBUG_DEFAULT_FLAGS, depending > - * on CONFIG_SLUB_DEBUG_ON). We can extended that to multiple lists as > - * long as there is no option specifying flags without a slab list. > - */ > - if (slab_list_specified) { > - if (!global_slub_debug_changed) > - global_flags = slub_debug; > - slub_debug_string = saved_str; > - } > -out: > - slub_debug = global_flags; > - if (slub_debug & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - if (slub_debug != 0 || slub_debug_string) > - static_branch_enable(&slub_debug_enabled); > - else > - static_branch_disable(&slub_debug_enabled); > - if ((static_branch_unlikely(&init_on_alloc) || > - static_branch_unlikely(&init_on_free)) && > - (slub_debug & SLAB_POISON)) > - pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n"); > - return 1; > -} > - > -__setup("slub_debug", setup_slub_debug); > - > -/* > - * kmem_cache_flags - apply debugging options to the cache > - * @object_size: the size of an object without meta data > - * @flags: flags to set > - * @name: name of the cache > - * > - * Debug option(s) are applied to @flags. In addition to the debug > - * option(s), if a slab name (or multiple) is specified i.e. > - * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... > - * then only the select slabs will receive the debug option(s). > - */ > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - char *iter; > - size_t len; > - char *next_block; > - slab_flags_t block_flags; > - slab_flags_t slub_debug_local = slub_debug; > - > - if (flags & SLAB_NO_USER_FLAGS) > - return flags; > - > - /* > - * If the slab cache is for debugging (e.g. kmemleak) then > - * don't store user (stack trace) information by default, > - * but let the user enable it via the command line below. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - slub_debug_local &= ~SLAB_STORE_USER; > - > - len = strlen(name); > - next_block = slub_debug_string; > - /* Go through all blocks of debug options, see if any matches our slab's name */ > - while (next_block) { > - next_block = parse_slub_debug_flags(next_block, &block_flags, &iter, false); > - if (!iter) > - continue; > - /* Found a block that has a slab list, search it */ > - while (*iter) { > - char *end, *glob; > - size_t cmplen; > - > - end = strchrnul(iter, ','); > - if (next_block && next_block < end) > - end = next_block - 1; > - > - glob = strnchr(iter, end - iter, '*'); > - if (glob) > - cmplen = glob - iter; > - else > - cmplen = max_t(size_t, len, (end - iter)); > - > - if (!strncmp(name, iter, cmplen)) { > - flags |= block_flags; > - return flags; > - } > - > - if (!*end || *end == ';') > - break; > - iter = end + 1; > - } > - } > - > - return flags | slub_debug_local; > -} > -#else /* !CONFIG_SLUB_DEBUG */ > -static inline void setup_object_debug(struct kmem_cache *s, void *object) {} > -static inline > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {} > - > -static inline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) { return true; } > - > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) { return true; } > - > -static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {} > -static inline int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) { return 1; } > -static inline depot_stack_handle_t set_track_prepare(void) { return 0; } > -static inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) {} > -static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > -#define slub_debug 0 > - > -#define disable_higher_order_debug 0 > - > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > - { return 0; } > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > - { return 0; } > -static inline void inc_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > - > -#ifndef CONFIG_SLUB_TINY > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - return false; > -} > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* > - * Hooks for other subsystems that check memory allocations. In a typical > - * production configuration these hooks all should produce no code at all. > - */ > -static __always_inline bool slab_free_hook(struct kmem_cache *s, > - void *x, bool init) > -{ > - kmemleak_free_recursive(x, s->flags); > - kmsan_slab_free(s, x); > - > - debug_check_no_locks_freed(x, s->object_size); > - > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(x, s->object_size); > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(s->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(x, s->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset's must be > - * kept together to avoid discrepancies in behavior. > - * > - * The initialization memset's clear the object and the metadata, > - * but don't touch the SLAB redzone. > - */ > - if (init) { > - int rsize; > - > - if (!kasan_has_integrated_init()) > - memset(kasan_reset_tag(x), 0, s->object_size); > - rsize = (s->flags & SLAB_RED_ZONE) ? s->red_left_pad : 0; > - memset((char *)kasan_reset_tag(x) + s->inuse, 0, > - s->size - s->inuse - rsize); > - } > - /* KASAN might put x into memory quarantine, delaying its reuse. */ > - return kasan_slab_free(s, x, init); > -} > - > -static inline bool slab_free_freelist_hook(struct kmem_cache *s, > - void **head, void **tail, > - int *cnt) > -{ > - > - void *object; > - void *next = *head; > - void *old_tail = *tail ? *tail : *head; > - > - if (is_kfence_address(next)) { > - slab_free_hook(s, next, false); > - return true; > - } > - > - /* Head and tail of the reconstructed freelist */ > - *head = NULL; > - *tail = NULL; > - > - do { > - object = next; > - next = get_freepointer(s, object); > - > - /* If object's reuse doesn't have to be delayed */ > - if (!slab_free_hook(s, object, slab_want_init_on_free(s))) { > - /* Move object to the new freelist */ > - set_freepointer(s, object, *head); > - *head = object; > - if (!*tail) > - *tail = object; > - } else { > - /* > - * Adjust the reconstructed freelist depth > - * accordingly if object's reuse is delayed. > - */ > - --(*cnt); > - } > - } while (object != old_tail); > - > - if (*head == *tail) > - *tail = NULL; > - > - return *head != NULL; > -} > - > -static void *setup_object(struct kmem_cache *s, void *object) > -{ > - setup_object_debug(s, object); > - object = kasan_init_slab_obj(s, object); > - if (unlikely(s->ctor)) { > - kasan_unpoison_object_data(s, object); > - s->ctor(object); > - kasan_poison_object_data(s, object); > - } > - return object; > -} > - > -/* > - * Slab allocation and freeing > - */ > -static inline struct slab *alloc_slab_page(gfp_t flags, int node, > - struct kmem_cache_order_objects oo) > -{ > - struct folio *folio; > - struct slab *slab; > - unsigned int order = oo_order(oo); > - > - if (node == NUMA_NO_NODE) > - folio = (struct folio *)alloc_pages(flags, order); > - else > - folio = (struct folio *)__alloc_pages_node(node, flags, order); > - > - if (!folio) > - return NULL; > - > - slab = folio_slab(folio); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - if (folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Pre-initialize the random sequence cache */ > -static int init_cache_random_seq(struct kmem_cache *s) > -{ > - unsigned int count = oo_objects(s->oo); > - int err; > - > - /* Bailout if already initialised */ > - if (s->random_seq) > - return 0; > - > - err = cache_random_seq_create(s, count, GFP_KERNEL); > - if (err) { > - pr_err("SLUB: Unable to initialize free list for %s\n", > - s->name); > - return err; > - } > - > - /* Transform to an offset on the set of pages */ > - if (s->random_seq) { > - unsigned int i; > - > - for (i = 0; i < count; i++) > - s->random_seq[i] *= s->size; > - } > - return 0; > -} > - > -/* Initialize each random sequence freelist per cache */ > -static void __init init_freelist_randomization(void) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - > - list_for_each_entry(s, &slab_caches, list) > - init_cache_random_seq(s); > - > - mutex_unlock(&slab_mutex); > -} > - > -/* Get the next entry on the pre-computed freelist randomized */ > -static void *next_freelist_entry(struct kmem_cache *s, struct slab *slab, > - unsigned long *pos, void *start, > - unsigned long page_limit, > - unsigned long freelist_count) > -{ > - unsigned int idx; > - > - /* > - * If the target page allocation failed, the number of objects on the > - * page might be smaller than the usual size defined by the cache. > - */ > - do { > - idx = s->random_seq[*pos]; > - *pos += 1; > - if (*pos >= freelist_count) > - *pos = 0; > - } while (unlikely(idx >= page_limit)); > - > - return (char *)start + idx; > -} > - > -/* Shuffle the single linked freelist based on a random pre-computed sequence */ > -static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - void *start; > - void *cur; > - void *next; > - unsigned long idx, pos, page_limit, freelist_count; > - > - if (slab->objects < 2 || !s->random_seq) > - return false; > - > - freelist_count = oo_objects(s->oo); > - pos = get_random_u32_below(freelist_count); > - > - page_limit = slab->objects * s->size; > - start = fixup_red_left(s, slab_address(slab)); > - > - /* First entry is used as the base of the freelist */ > - cur = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - cur = setup_object(s, cur); > - slab->freelist = cur; > - > - for (idx = 1; idx < slab->objects; idx++) { > - next = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - next = setup_object(s, next); > - set_freepointer(s, cur, next); > - cur = next; > - } > - set_freepointer(s, cur, NULL); > - > - return true; > -} > -#else > -static inline int init_cache_random_seq(struct kmem_cache *s) > -{ > - return 0; > -} > -static inline void init_freelist_randomization(void) { } > -static inline bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - struct slab *slab; > - struct kmem_cache_order_objects oo = s->oo; > - gfp_t alloc_gfp; > - void *start, *p, *next; > - int idx; > - bool shuffle; > - > - flags &= gfp_allowed_mask; > - > - flags |= s->allocflags; > - > - /* > - * Let the initial higher-order allocation fail under memory pressure > - * so we fall-back to the minimum order allocation. > - */ > - alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; > - if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) > - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_RECLAIM; > - > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) { > - oo = s->min; > - alloc_gfp = flags; > - /* > - * Allocation may have failed due to fragmentation. > - * Try a lower order alloc if possible > - */ > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) > - return NULL; > - stat(s, ORDER_FALLBACK); > - } > - > - slab->objects = oo_objects(oo); > - slab->inuse = 0; > - slab->frozen = 0; > - > - account_slab(slab, oo_order(oo), s, flags); > - > - slab->slab_cache = s; > - > - kasan_poison_slab(slab); > - > - start = slab_address(slab); > - > - setup_slab_debug(s, slab, start); > - > - shuffle = shuffle_freelist(s, slab); > - > - if (!shuffle) { > - start = fixup_red_left(s, start); > - start = setup_object(s, start); > - slab->freelist = start; > - for (idx = 0, p = start; idx < slab->objects - 1; idx++) { > - next = p + s->size; > - next = setup_object(s, next); > - set_freepointer(s, p, next); > - p = next; > - } > - set_freepointer(s, p, NULL); > - } > - > - return slab; > -} > - > -static struct slab *new_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); > - > - return allocate_slab(s, > - flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); > -} > - > -static void __free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - struct folio *folio = slab_folio(slab); > - int order = folio_order(folio); > - int pages = 1 << order; > - > - __slab_clear_pfmemalloc(slab); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += pages; > - unaccount_slab(slab, order, s); > - __free_pages(&folio->page, order); > -} > - > -static void rcu_free_slab(struct rcu_head *h) > -{ > - struct slab *slab = container_of(h, struct slab, rcu_head); > - > - __free_slab(slab->slab_cache, slab); > -} > - > -static void free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - if (kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) { > - void *p; > - > - slab_pad_check(s, slab); > - for_each_object(p, s, slab_address(slab), slab->objects) > - check_object(s, slab, p, SLUB_RED_INACTIVE); > - } > - > - if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, rcu_free_slab); > - else > - __free_slab(s, slab); > -} > - > -static void discard_slab(struct kmem_cache *s, struct slab *slab) > -{ > - dec_slabs_node(s, slab_nid(slab), slab->objects); > - free_slab(s, slab); > -} > - > -/* > - * Management of partially allocated slabs. > - */ > -static inline void > -__add_partial(struct kmem_cache_node *n, struct slab *slab, int tail) > -{ > - n->nr_partial++; > - if (tail == DEACTIVATE_TO_TAIL) > - list_add_tail(&slab->slab_list, &n->partial); > - else > - list_add(&slab->slab_list, &n->partial); > -} > - > -static inline void add_partial(struct kmem_cache_node *n, > - struct slab *slab, int tail) > -{ > - lockdep_assert_held(&n->list_lock); > - __add_partial(n, slab, tail); > -} > - > -static inline void remove_partial(struct kmem_cache_node *n, > - struct slab *slab) > -{ > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > - n->nr_partial--; > -} > - > -/* > - * Called only for kmem_cache_debug() caches instead of acquire_slab(), with a > - * slab from the n->partial list. Remove only a single object from the slab, do > - * the alloc_debug_processing() checks and leave the slab on the list, or move > - * it to full list if it was the last free object. > - */ > -static void *alloc_single_from_partial(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, int orig_size) > -{ > - void *object; > - > - lockdep_assert_held(&n->list_lock); > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse++; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) { > - remove_partial(n, slab); > - return NULL; > - } > - > - if (slab->inuse == slab->objects) { > - remove_partial(n, slab); > - add_full(s, n, slab); > - } > - > - return object; > -} > - > -/* > - * Called only for kmem_cache_debug() caches to allocate from a freshly > - * allocated slab. Allocate a single object instead of whole freelist > - * and put the slab to the partial (or full) list. > - */ > -static void *alloc_single_from_new_slab(struct kmem_cache *s, > - struct slab *slab, int orig_size) > -{ > - int nid = slab_nid(slab); > - struct kmem_cache_node *n = get_node(s, nid); > - unsigned long flags; > - void *object; > - > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse = 1; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) > - /* > - * It's not really expected that this would fail on a > - * freshly allocated slab, but a concurrent memory > - * corruption in theory could cause that. > - */ > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (slab->inuse == slab->objects) > - add_full(s, n, slab); > - else > - add_partial(n, slab, DEACTIVATE_TO_HEAD); > - > - inc_slabs_node(s, nid, slab->objects); > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - return object; > -} > - > -/* > - * Remove slab from the partial list, freeze it and > - * return the pointer to the freelist. > - * > - * Returns a list of objects or NULL if it fails. > - */ > -static inline void *acquire_slab(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, > - int mode) > -{ > - void *freelist; > - unsigned long counters; > - struct slab new; > - > - lockdep_assert_held(&n->list_lock); > - > - /* > - * Zap the freelist and set the frozen bit. > - * The old freelist is the list of objects for the > - * per cpu allocation list. > - */ > - freelist = slab->freelist; > - counters = slab->counters; > - new.counters = counters; > - if (mode) { > - new.inuse = slab->objects; > - new.freelist = NULL; > - } else { > - new.freelist = freelist; > - } > - > - VM_BUG_ON(new.frozen); > - new.frozen = 1; > - > - if (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - new.freelist, new.counters, > - "acquire_slab")) > - return NULL; > - > - remove_partial(n, slab); > - WARN_ON(!freelist); > - return freelist; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain); > -#else > -static inline void put_cpu_partial(struct kmem_cache *s, struct slab *slab, > - int drain) { } > -#endif > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags); > - > -/* > - * Try to allocate a partial slab from a specific node. > - */ > -static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, > - struct partial_context *pc) > -{ > - struct slab *slab, *slab2; > - void *object = NULL; > - unsigned long flags; > - unsigned int partial_slabs = 0; > - > - /* > - * Racy check. If we mistakenly see no partial slabs then we > - * just allocate an empty slab. If we mistakenly try to get a > - * partial slab and there is none available then get_partial() > - * will return NULL. > - */ > - if (!n || !n->nr_partial) > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry_safe(slab, slab2, &n->partial, slab_list) { > - void *t; > - > - if (!pfmemalloc_match(slab, pc->flags)) > - continue; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - object = alloc_single_from_partial(s, n, slab, > - pc->orig_size); > - if (object) > - break; > - continue; > - } > - > - t = acquire_slab(s, n, slab, object == NULL); > - if (!t) > - break; > - > - if (!object) { > - *pc->slab = slab; > - stat(s, ALLOC_FROM_PARTIAL); > - object = t; > - } else { > - put_cpu_partial(s, slab, 0); > - stat(s, CPU_PARTIAL_NODE); > - partial_slabs++; > - } > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - if (!kmem_cache_has_cpu_partial(s) > - || partial_slabs > s->cpu_partial_slabs / 2) > - break; > -#else > - break; > -#endif > - > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return object; > -} > - > -/* > - * Get a slab from somewhere. Search in increasing NUMA distances. > - */ > -static void *get_any_partial(struct kmem_cache *s, struct partial_context *pc) > -{ > -#ifdef CONFIG_NUMA > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(pc->flags); > - void *object; > - unsigned int cpuset_mems_cookie; > - > - /* > - * The defrag ratio allows a configuration of the tradeoffs between > - * inter node defragmentation and node local allocations. A lower > - * defrag_ratio increases the tendency to do local allocations > - * instead of attempting to obtain partial slabs from other nodes. > - * > - * If the defrag_ratio is set to 0 then kmalloc() always > - * returns node local objects. If the ratio is higher then kmalloc() > - * may return off node objects because partial slabs are obtained > - * from other nodes and filled up. > - * > - * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 > - * (which makes defrag_ratio = 1000) then every (well almost) > - * allocation will first attempt to defrag slab caches on other nodes. > - * This means scanning over all nodes to look for partial slabs which > - * may be expensive if we do it every time we are trying to find a slab > - * with available objects. > - */ > - if (!s->remote_node_defrag_ratio || > - get_cycles() % 1024 > s->remote_node_defrag_ratio) > - return NULL; > - > - do { > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), pc->flags); > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - struct kmem_cache_node *n; > - > - n = get_node(s, zone_to_nid(zone)); > - > - if (n && cpuset_zone_allowed(zone, pc->flags) && > - n->nr_partial > s->min_partial) { > - object = get_partial_node(s, n, pc); > - if (object) { > - /* > - * Don't check read_mems_allowed_retry() > - * here - if mems_allowed was updated in > - * parallel, that was a harmless race > - * between allocation and the cpuset > - * update > - */ > - return object; > - } > - } > - } > - } while (read_mems_allowed_retry(cpuset_mems_cookie)); > -#endif /* CONFIG_NUMA */ > - return NULL; > -} > - > -/* > - * Get a partial slab, lock it and return it. > - */ > -static void *get_partial(struct kmem_cache *s, int node, struct partial_context *pc) > -{ > - void *object; > - int searchnode = node; > - > - if (node == NUMA_NO_NODE) > - searchnode = numa_mem_id(); > - > - object = get_partial_node(s, get_node(s, searchnode), pc); > - if (object || node != NUMA_NO_NODE) > - return object; > - > - return get_any_partial(s, pc); > -} > - > -#ifndef CONFIG_SLUB_TINY > - > -#ifdef CONFIG_PREEMPTION > -/* > - * Calculate the next globally unique transaction for disambiguation > - * during cmpxchg. The transactions start with the cpu number and are then > - * incremented by CONFIG_NR_CPUS. > - */ > -#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) > -#else > -/* > - * No preemption supported therefore also no need to check for > - * different cpus. > - */ > -#define TID_STEP 1 > -#endif /* CONFIG_PREEMPTION */ > - > -static inline unsigned long next_tid(unsigned long tid) > -{ > - return tid + TID_STEP; > -} > - > -#ifdef SLUB_DEBUG_CMPXCHG > -static inline unsigned int tid_to_cpu(unsigned long tid) > -{ > - return tid % TID_STEP; > -} > - > -static inline unsigned long tid_to_event(unsigned long tid) > -{ > - return tid / TID_STEP; > -} > -#endif > - > -static inline unsigned int init_tid(int cpu) > -{ > - return cpu; > -} > - > -static inline void note_cmpxchg_failure(const char *n, > - const struct kmem_cache *s, unsigned long tid) > -{ > -#ifdef SLUB_DEBUG_CMPXCHG > - unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); > - > - pr_info("%s %s: cmpxchg redo ", n, s->name); > - > -#ifdef CONFIG_PREEMPTION > - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) > - pr_warn("due to cpu change %d -> %d\n", > - tid_to_cpu(tid), tid_to_cpu(actual_tid)); > - else > -#endif > - if (tid_to_event(tid) != tid_to_event(actual_tid)) > - pr_warn("due to cpu running other code. Event %ld->%ld\n", > - tid_to_event(tid), tid_to_event(actual_tid)); > - else > - pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", > - actual_tid, tid, next_tid(tid)); > -#endif > - stat(s, CMPXCHG_DOUBLE_CPU_FAIL); > -} > - > -static void init_kmem_cache_cpus(struct kmem_cache *s) > -{ > - int cpu; > - struct kmem_cache_cpu *c; > - > - for_each_possible_cpu(cpu) { > - c = per_cpu_ptr(s->cpu_slab, cpu); > - local_lock_init(&c->lock); > - c->tid = init_tid(cpu); > - } > -} > - > -/* > - * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist, > - * unfreezes the slabs and puts it on the proper list. > - * Assumes the slab has been already safely taken away from kmem_cache_cpu > - * by the caller. > - */ > -static void deactivate_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist) > -{ > - enum slab_modes { M_NONE, M_PARTIAL, M_FREE, M_FULL_NOLIST }; > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - int free_delta = 0; > - enum slab_modes mode = M_NONE; > - void *nextfree, *freelist_iter, *freelist_tail; > - int tail = DEACTIVATE_TO_HEAD; > - unsigned long flags = 0; > - struct slab new; > - struct slab old; > - > - if (slab->freelist) { > - stat(s, DEACTIVATE_REMOTE_FREES); > - tail = DEACTIVATE_TO_TAIL; > - } > - > - /* > - * Stage one: Count the objects on cpu's freelist as free_delta and > - * remember the last object in freelist_tail for later splicing. > - */ > - freelist_tail = NULL; > - freelist_iter = freelist; > - while (freelist_iter) { > - nextfree = get_freepointer(s, freelist_iter); > - > - /* > - * If 'nextfree' is invalid, it is possible that the object at > - * 'freelist_iter' is already corrupted. So isolate all objects > - * starting at 'freelist_iter' by skipping them. > - */ > - if (freelist_corrupted(s, slab, &freelist_iter, nextfree)) > - break; > - > - freelist_tail = freelist_iter; > - free_delta++; > - > - freelist_iter = nextfree; > - } > - > - /* > - * Stage two: Unfreeze the slab while splicing the per-cpu > - * freelist to the head of slab's freelist. > - * > - * Ensure that the slab is unfrozen while the list presence > - * reflects the actual number of objects during unfreeze. > - * > - * We first perform cmpxchg holding lock and insert to list > - * when it succeed. If there is mismatch then the slab is not > - * unfrozen and number of objects in the slab may have changed. > - * Then release lock and retry cmpxchg again. > - */ > -redo: > - > - old.freelist = READ_ONCE(slab->freelist); > - old.counters = READ_ONCE(slab->counters); > - VM_BUG_ON(!old.frozen); > - > - /* Determine target state of the slab */ > - new.counters = old.counters; > - if (freelist_tail) { > - new.inuse -= free_delta; > - set_freepointer(s, freelist_tail, old.freelist); > - new.freelist = freelist; > - } else > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - if (!new.inuse && n->nr_partial >= s->min_partial) { > - mode = M_FREE; > - } else if (new.freelist) { > - mode = M_PARTIAL; > - /* > - * Taking the spinlock removes the possibility that > - * acquire_slab() will see a slab that is frozen > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - } else { > - mode = M_FULL_NOLIST; > - } > - > - > - if (!cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")) { > - if (mode == M_PARTIAL) > - spin_unlock_irqrestore(&n->list_lock, flags); > - goto redo; > - } > - > - > - if (mode == M_PARTIAL) { > - add_partial(n, slab, tail); > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, tail); > - } else if (mode == M_FREE) { > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } else if (mode == M_FULL_NOLIST) { > - stat(s, DEACTIVATE_FULL); > - } > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab) > -{ > - struct kmem_cache_node *n = NULL, *n2 = NULL; > - struct slab *slab, *slab_to_discard = NULL; > - unsigned long flags = 0; > - > - while (partial_slab) { > - struct slab new; > - struct slab old; > - > - slab = partial_slab; > - partial_slab = slab->next; > - > - n2 = get_node(s, slab_nid(slab)); > - if (n != n2) { > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - n = n2; > - spin_lock_irqsave(&n->list_lock, flags); > - } > - > - do { > - > - old.freelist = slab->freelist; > - old.counters = slab->counters; > - VM_BUG_ON(!old.frozen); > - > - new.counters = old.counters; > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - } while (!__cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")); > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { > - slab->next = slab_to_discard; > - slab_to_discard = slab; > - } else { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } > - > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - while (slab_to_discard) { > - slab = slab_to_discard; > - slab_to_discard = slab_to_discard->next; > - > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } > -} > - > -/* > - * Unfreeze all the cpu partial slabs. > - */ > -static void unfreeze_partials(struct kmem_cache *s) > -{ > - struct slab *partial_slab; > - unsigned long flags; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - partial_slab = this_cpu_read(s->cpu_slab->partial); > - this_cpu_write(s->cpu_slab->partial, NULL); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -static void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) > -{ > - struct slab *partial_slab; > - > - partial_slab = slub_percpu_partial(c); > - c->partial = NULL; > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -/* > - * Put a slab that was just frozen (in __slab_free|get_partial_node) into a > - * partial slab slot if available. > - * > - * If we did not find a slot then simply move all the partials to the > - * per node partial list. > - */ > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain) > -{ > - struct slab *oldslab; > - struct slab *slab_to_unfreeze = NULL; > - unsigned long flags; > - int slabs = 0; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - oldslab = this_cpu_read(s->cpu_slab->partial); > - > - if (oldslab) { > - if (drain && oldslab->slabs >= s->cpu_partial_slabs) { > - /* > - * Partial array is full. Move the existing set to the > - * per node partial list. Postpone the actual unfreezing > - * outside of the critical section. > - */ > - slab_to_unfreeze = oldslab; > - oldslab = NULL; > - } else { > - slabs = oldslab->slabs; > - } > - } > - > - slabs++; > - > - slab->slabs = slabs; > - slab->next = oldslab; > - > - this_cpu_write(s->cpu_slab->partial, slab); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab_to_unfreeze) { > - __unfreeze_partials(s, slab_to_unfreeze); > - stat(s, CPU_PARTIAL_DRAIN); > - } > -} > - > -#else /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void unfreeze_partials(struct kmem_cache *s) { } > -static inline void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) { } > - > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) > -{ > - unsigned long flags; > - struct slab *slab; > - void *freelist; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - slab = c->slab; > - freelist = c->freelist; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > -} > - > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - void *freelist = c->freelist; > - struct slab *slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > - > - unfreeze_partials_cpu(s, c); > -} > - > -struct slub_flush_work { > - struct work_struct work; > - struct kmem_cache *s; > - bool skip; > -}; > - > -/* > - * Flush cpu slab. > - * > - * Called from CPU work handler with migration disabled. > - */ > -static void flush_cpu_slab(struct work_struct *w) > -{ > - struct kmem_cache *s; > - struct kmem_cache_cpu *c; > - struct slub_flush_work *sfw; > - > - sfw = container_of(w, struct slub_flush_work, work); > - > - s = sfw->s; > - c = this_cpu_ptr(s->cpu_slab); > - > - if (c->slab) > - flush_slab(s, c); > - > - unfreeze_partials(s); > -} > - > -static bool has_cpu_slab(int cpu, struct kmem_cache *s) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - > - return c->slab || slub_percpu_partial(c); > -} > - > -static DEFINE_MUTEX(flush_lock); > -static DEFINE_PER_CPU(struct slub_flush_work, slub_flush); > - > -static void flush_all_cpus_locked(struct kmem_cache *s) > -{ > - struct slub_flush_work *sfw; > - unsigned int cpu; > - > - lockdep_assert_cpus_held(); > - mutex_lock(&flush_lock); > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (!has_cpu_slab(cpu, s)) { > - sfw->skip = true; > - continue; > - } > - INIT_WORK(&sfw->work, flush_cpu_slab); > - sfw->skip = false; > - sfw->s = s; > - queue_work_on(cpu, flushwq, &sfw->work); > - } > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (sfw->skip) > - continue; > - flush_work(&sfw->work); > - } > - > - mutex_unlock(&flush_lock); > -} > - > -static void flush_all(struct kmem_cache *s) > -{ > - cpus_read_lock(); > - flush_all_cpus_locked(s); > - cpus_read_unlock(); > -} > - > -/* > - * Use the cpu notifier to insure that the cpu slabs are flushed when > - * necessary. > - */ > -static int slub_cpu_dead(unsigned int cpu) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) > - __flush_cpu_slab(s, cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > - > -#else /* CONFIG_SLUB_TINY */ > -static inline void flush_all_cpus_locked(struct kmem_cache *s) { } > -static inline void flush_all(struct kmem_cache *s) { } > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { } > -static inline int slub_cpu_dead(unsigned int cpu) { return 0; } > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * Check if the objects in a per cpu structure fit numa > - * locality expectations. > - */ > -static inline int node_match(struct slab *slab, int node) > -{ > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE && slab_nid(slab) != node) > - return 0; > -#endif > - return 1; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static int count_free(struct slab *slab) > -{ > - return slab->objects - slab->inuse; > -} > - > -static inline unsigned long node_nr_objs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->total_objects); > -} > - > -/* Supports checking bulk free of a constructed freelist */ > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) > -{ > - bool checks_ok = false; > - void *object = head; > - int cnt = 0; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!check_slab(s, slab)) > - goto out; > - } > - > - if (slab->inuse < *bulk_cnt) { > - slab_err(s, slab, "Slab has %d allocated objects but %d are to be freed\n", > - slab->inuse, *bulk_cnt); > - goto out; > - } > - > -next_object: > - > - if (++cnt > *bulk_cnt) > - goto out_cnt; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!free_consistency_checks(s, slab, object, addr)) > - goto out; > - } > - > - if (s->flags & SLAB_STORE_USER) > - set_track_update(s, object, TRACK_FREE, addr, handle); > - trace(s, slab, object, 0); > - /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ > - init_object(s, object, SLUB_RED_INACTIVE); > - > - /* Reached end of constructed freelist yet? */ > - if (object != tail) { > - object = get_freepointer(s, object); > - goto next_object; > - } > - checks_ok = true; > - > -out_cnt: > - if (cnt != *bulk_cnt) { > - slab_err(s, slab, "Bulk free expected %d objects but found %d\n", > - *bulk_cnt, cnt); > - *bulk_cnt = cnt; > - } > - > -out: > - > - if (!checks_ok) > - slab_fix(s, "Object at 0x%p not freed", object); > - > - return checks_ok; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#if defined(CONFIG_SLUB_DEBUG) || defined(SLAB_SUPPORTS_SYSFS) > -static unsigned long count_partial(struct kmem_cache_node *n, > - int (*get_count)(struct slab *)) > -{ > - unsigned long flags; > - unsigned long x = 0; > - struct slab *slab; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - x += get_count(slab); > - spin_unlock_irqrestore(&n->list_lock, flags); > - return x; > -} > -#endif /* CONFIG_SLUB_DEBUG || SLAB_SUPPORTS_SYSFS */ > - > -#ifdef CONFIG_SLUB_DEBUG > -static noinline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) > -{ > - static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - int node; > - struct kmem_cache_node *n; > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) > - return; > - > - pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", > - s->name, s->object_size, s->size, oo_order(s->oo), > - oo_order(s->min)); > - > - if (oo_order(s->min) > get_order(s->object_size)) > - pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", > - s->name); > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long nr_slabs; > - unsigned long nr_objs; > - unsigned long nr_free; > - > - nr_free = count_partial(n, count_free); > - nr_slabs = node_nr_slabs(n); > - nr_objs = node_nr_objs(n); > - > - pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", > - node, nr_slabs, nr_objs, nr_free); > - } > -} > -#else /* CONFIG_SLUB_DEBUG */ > -static inline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) { } > -#endif > - > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags) > -{ > - if (unlikely(slab_test_pfmemalloc(slab))) > - return gfp_pfmemalloc_allowed(gfpflags); > - > - return true; > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Check the slab->freelist and either transfer the freelist to the > - * per cpu freelist or deactivate the slab. > - * > - * The slab is still frozen if the return value is not NULL. > - * > - * If this function returns NULL then the slab has been unfrozen. > - */ > -static inline void *get_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - struct slab new; > - unsigned long counters; > - void *freelist; > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - do { > - freelist = slab->freelist; > - counters = slab->counters; > - > - new.counters = counters; > - VM_BUG_ON(!new.frozen); > - > - new.inuse = slab->objects; > - new.frozen = freelist != NULL; > - > - } while (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - NULL, new.counters, > - "get_freelist")); > - > - return freelist; > -} > - > -/* > - * Slow path. The lockless freelist is empty or we need to perform > - * debugging duties. > - * > - * Processing is still very fast if new objects have been freed to the > - * regular freelist. In that case we simply take over the regular freelist > - * as the lockless freelist and zap the regular freelist. > - * > - * If that is not working then we fall back to the partial lists. We take the > - * first element of the freelist as the object to allocate now and move the > - * rest of the freelist to the lockless freelist. > - * > - * And if we were unable to get a new slab from the partial slab lists then > - * we need to allocate a new slab. This is the slowest path since it involves > - * a call to the page allocator and the setup of a new slab. > - * > - * Version of __slab_alloc to use when we know that preemption is > - * already disabled (which is the case for bulk allocation). > - */ > -static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *freelist; > - struct slab *slab; > - unsigned long flags; > - struct partial_context pc; > - > - stat(s, ALLOC_SLOWPATH); > - > -reread_slab: > - > - slab = READ_ONCE(c->slab); > - if (!slab) { > - /* > - * if the node is not online or has no normal memory, just > - * ignore the node constraint > - */ > - if (unlikely(node != NUMA_NO_NODE && > - !node_isset(node, slab_nodes))) > - node = NUMA_NO_NODE; > - goto new_slab; > - } > -redo: > - > - if (unlikely(!node_match(slab, node))) { > - /* > - * same as above but node_match() being false already > - * implies node != NUMA_NO_NODE > - */ > - if (!node_isset(node, slab_nodes)) { > - node = NUMA_NO_NODE; > - } else { > - stat(s, ALLOC_NODE_MISMATCH); > - goto deactivate_slab; > - } > - } > - > - /* > - * By rights, we should be searching for a slab page that was > - * PFMEMALLOC but right now, we are losing the pfmemalloc > - * information when the page leaves the per-cpu allocator > - */ > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) > - goto deactivate_slab; > - > - /* must check again c->slab in case we got preempted and it changed */ > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(slab != c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - if (freelist) > - goto load_freelist; > - > - freelist = get_freelist(s, slab); > - > - if (!freelist) { > - c->slab = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, DEACTIVATE_BYPASS); > - goto new_slab; > - } > - > - stat(s, ALLOC_REFILL); > - > -load_freelist: > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - /* > - * freelist is pointing to the list of objects to be used. > - * slab is pointing to the slab from which the objects are obtained. > - * That slab must be frozen for per cpu allocations to work. > - */ > - VM_BUG_ON(!c->slab->frozen); > - c->freelist = get_freepointer(s, freelist); > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - return freelist; > - > -deactivate_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (slab != c->slab) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - deactivate_slab(s, slab, freelist); > - > -new_slab: > - > - if (slub_percpu_partial(c)) { > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - if (unlikely(!slub_percpu_partial(c))) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - /* we were preempted and partial list got empty */ > - goto new_objects; > - } > - > - slab = c->slab = slub_percpu_partial(c); > - slub_set_percpu_partial(c, slab); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, CPU_PARTIAL_ALLOC); > - goto redo; > - } > - > -new_objects: > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - freelist = get_partial(s, node, &pc); > - if (freelist) > - goto check_new_slab; > - > - slub_put_cpu_ptr(s->cpu_slab); > - slab = new_slab(s, gfpflags, node); > - c = slub_get_cpu_ptr(s->cpu_slab); > - > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - stat(s, ALLOC_SLAB); > - > - if (kmem_cache_debug(s)) { > - freelist = alloc_single_from_new_slab(s, slab, orig_size); > - > - if (unlikely(!freelist)) > - goto new_objects; > - > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - /* > - * No other reference to the slab yet so we can > - * muck around with it freely without cmpxchg > - */ > - freelist = slab->freelist; > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab->frozen = 1; > - > - inc_slabs_node(s, slab_nid(slab), slab->objects); > - > -check_new_slab: > - > - if (kmem_cache_debug(s)) { > - /* > - * For debug caches here we had to go through > - * alloc_single_from_partial() so just store the tracking info > - * and return the object > - */ > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) { > - /* > - * For !pfmemalloc_match() case we don't load freelist so that > - * we don't make further mismatched allocations easier. > - */ > - deactivate_slab(s, slab, get_freepointer(s, freelist)); > - return freelist; > - } > - > -retry_load_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - void *flush_freelist = c->freelist; > - struct slab *flush_slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - deactivate_slab(s, flush_slab, flush_freelist); > - > - stat(s, CPUSLAB_FLUSH); > - > - goto retry_load_slab; > - } > - c->slab = slab; > - > - goto load_freelist; > -} > - > -/* > - * A wrapper for ___slab_alloc() for contexts where preemption is not yet > - * disabled. Compensates for possible cpu changes by refetching the per cpu area > - * pointer. > - */ > -static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *p; > - > -#ifdef CONFIG_PREEMPT_COUNT > - /* > - * We may have been preempted and rescheduled on a different > - * cpu before disabling preemption. Need to reload cpu area > - * pointer. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > -#endif > - > - p = ___slab_alloc(s, gfpflags, node, addr, c, orig_size); > -#ifdef CONFIG_PREEMPT_COUNT > - slub_put_cpu_ptr(s->cpu_slab); > -#endif > - return p; > -} > - > -static __always_inline void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct kmem_cache_cpu *c; > - struct slab *slab; > - unsigned long tid; > - void *object; > - > -redo: > - /* > - * Must read kmem_cache cpu data via this cpu ptr. Preemption is > - * enabled. We may switch back and forth between cpus while > - * reading from one cpu area. That does not matter as long > - * as we end up on the original cpu again when doing the cmpxchg. > - * > - * We must guarantee that tid and kmem_cache_cpu are retrieved on the > - * same cpu. We read first the kmem_cache_cpu pointer and use it to read > - * the tid. If we are preempted and switched to another cpu between the > - * two reads, it's OK as the two are still associated with the same cpu > - * and cmpxchg later will validate the cpu. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* > - * Irqless object alloc/free algorithm used here depends on sequence > - * of fetching cpu_slab's data. tid should be fetched before anything > - * on c to guarantee that object and slab associated with previous tid > - * won't be used with current tid. If we fetch tid first, object and > - * slab could be one associated with next tid and our alloc/free > - * request will be failed. In this case, we will retry. So, no problem. > - */ > - barrier(); > - > - /* > - * The transaction ids are globally unique per cpu and per operation on > - * a per cpu queue. Thus they can be guarantee that the cmpxchg_double > - * occurs on the right processor and that there was no operation on the > - * linked list in between. > - */ > - > - object = c->freelist; > - slab = c->slab; > - > - if (!USE_LOCKLESS_FAST_PATH() || > - unlikely(!object || !slab || !node_match(slab, node))) { > - object = __slab_alloc(s, gfpflags, node, addr, c, orig_size); > - } else { > - void *next_object = get_freepointer_safe(s, object); > - > - /* > - * The cmpxchg will only match if there was no additional > - * operation and if we are on the right processor. > - * > - * The cmpxchg does the following atomically (without lock > - * semantics!) > - * 1. Relocate first pointer to the current per cpu area. > - * 2. Verify that tid and freelist have not been changed > - * 3. If they were not changed replace tid and freelist > - * > - * Since this is without lock semantics the protection is only > - * against code executing on this cpu *not* from access by > - * other cpus. > - */ > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - object, tid, > - next_object, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_alloc", s, tid); > - goto redo; > - } > - prefetch_freepointer(s, next_object); > - stat(s, ALLOC_FASTPATH); > - } > - > - return object; > -} > -#else /* CONFIG_SLUB_TINY */ > -static void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct partial_context pc; > - struct slab *slab; > - void *object; > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - object = get_partial(s, node, &pc); > - > - if (object) > - return object; > - > - slab = new_slab(s, gfpflags, node); > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - object = alloc_single_from_new_slab(s, slab, orig_size); > - > - return object; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * If the object has been wiped upon free, make sure it's fully initialized by > - * zeroing out freelist pointer. > - */ > -static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, > - void *obj) > -{ > - if (unlikely(slab_want_init_on_free(s)) && obj) > - memset((void *)((char *)kasan_reset_tag(obj) + s->offset), > - 0, sizeof(void *)); > -} > - > -/* > - * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) > - * have the fastpath folded into their functions. So no function call > - * overhead for requests that can be satisfied on the fastpath. > - * > - * The fastpath works by first checking if the lockless freelist can be used. > - * If not then __slab_alloc is called for slow processing. > - * > - * Otherwise we can simply pick the next object from the lockless free list. > - */ > -static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - void *object; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); > - if (!s) > - return NULL; > - > - object = kfence_alloc(s, orig_size, gfpflags); > - if (unlikely(object)) > - goto out; > - > - object = __slab_alloc_node(s, gfpflags, node, addr, orig_size); > - > - maybe_wipe_obj_freeptr(s, object); > - init = slab_want_init_on_alloc(gfpflags, s); > - > -out: > - /* > - * When init equals 'true', like for kzalloc() family, only > - * @orig_size bytes might be zeroed instead of s->object_size > - */ > - slab_post_alloc_hook(s, objcg, gfpflags, 1, &object, init, orig_size); > - > - return object; > -} > - > -static __fastpath_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, unsigned long addr, size_t orig_size) > -{ > - return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); > -} > - > -static __fastpath_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, NULL, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, lru, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(s, NULL, gfpflags, node, > - caller, orig_size); > -} > - > -void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) > -{ > - void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, node); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static noinline void free_to_partial_list( > - struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int bulk_cnt, > - unsigned long addr) > -{ > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - struct slab *slab_free = NULL; > - int cnt = bulk_cnt; > - unsigned long flags; > - depot_stack_handle_t handle = 0; > - > - if (s->flags & SLAB_STORE_USER) > - handle = set_track_prepare(); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (free_debug_processing(s, slab, head, tail, &cnt, addr, handle)) { > - void *prior = slab->freelist; > - > - /* Perform the actual freeing while we still hold the locks */ > - slab->inuse -= cnt; > - set_freepointer(s, tail, prior); > - slab->freelist = head; > - > - /* > - * If the slab is empty, and node's partial list is full, > - * it should be discarded anyway no matter it's on full or > - * partial list. > - */ > - if (slab->inuse == 0 && n->nr_partial >= s->min_partial) > - slab_free = slab; > - > - if (!prior) { > - /* was on full list */ > - remove_full(s, n, slab); > - if (!slab_free) { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } else if (slab_free) { > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } > - } > - > - if (slab_free) { > - /* > - * Update the counters while still holding n->list_lock to > - * prevent spurious validation warnings > - */ > - dec_slabs_node(s, slab_nid(slab_free), slab_free->objects); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - if (slab_free) { > - stat(s, FREE_SLAB); > - free_slab(s, slab_free); > - } > -} > - > -/* > - * Slow path handling. This may still be called frequently since objects > - * have a longer lifetime than the cpu slabs in most processing loads. > - * > - * So we still attempt to reduce cache line usage. Just take the slab > - * lock and free the item. If there is no additional partial slab > - * handling required then we can return immediately. > - */ > -static void __slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int cnt, > - unsigned long addr) > - > -{ > - void *prior; > - int was_frozen; > - struct slab new; > - unsigned long counters; > - struct kmem_cache_node *n = NULL; > - unsigned long flags; > - > - stat(s, FREE_SLOWPATH); > - > - if (kfence_free(head)) > - return; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - free_to_partial_list(s, slab, head, tail, cnt, addr); > - return; > - } > - > - do { > - if (unlikely(n)) { > - spin_unlock_irqrestore(&n->list_lock, flags); > - n = NULL; > - } > - prior = slab->freelist; > - counters = slab->counters; > - set_freepointer(s, tail, prior); > - new.counters = counters; > - was_frozen = new.frozen; > - new.inuse -= cnt; > - if ((!new.inuse || !prior) && !was_frozen) { > - > - if (kmem_cache_has_cpu_partial(s) && !prior) { > - > - /* > - * Slab was on no list before and will be > - * partially empty > - * We can defer the list move and instead > - * freeze it. > - */ > - new.frozen = 1; > - > - } else { /* Needs to be taken off a list */ > - > - n = get_node(s, slab_nid(slab)); > - /* > - * Speculatively acquire the list_lock. > - * If the cmpxchg does not succeed then we may > - * drop the list_lock without any processing. > - * > - * Otherwise the list_lock will synchronize with > - * other processors updating the list of slabs. > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - > - } > - } > - > - } while (!cmpxchg_double_slab(s, slab, > - prior, counters, > - head, new.counters, > - "__slab_free")); > - > - if (likely(!n)) { > - > - if (likely(was_frozen)) { > - /* > - * The list lock was not taken therefore no list > - * activity can be necessary. > - */ > - stat(s, FREE_FROZEN); > - } else if (new.frozen) { > - /* > - * If we just froze the slab then put it onto the > - * per cpu partial list. > - */ > - put_cpu_partial(s, slab, 1); > - stat(s, CPU_PARTIAL_FREE); > - } > - > - return; > - } > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) > - goto slab_empty; > - > - /* > - * Objects left in the slab. If it was not on the partial list before > - * then add it. > - */ > - if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { > - remove_full(s, n, slab); > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return; > - > -slab_empty: > - if (prior) { > - /* > - * Slab on the partial list. > - */ > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } else { > - /* Slab must be on the full list */ > - remove_full(s, n, slab); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, FREE_SLAB); > - discard_slab(s, slab); > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Fastpath with forced inlining to produce a kfree and kmem_cache_free that > - * can perform fastpath freeing without additional function calls. > - * > - * The fastpath is only possible if we are freeing to the current cpu slab > - * of this processor. This typically the case if we have just allocated > - * the item before. > - * > - * If fastpath is not possible then fall back to __slab_free where we deal > - * with all sorts of special processing. > - * > - * Bulk free of a freelist with several objects (all pointing to the > - * same slab) possible by specifying head and tail ptr, plus objects > - * count (cnt). Bulk free indicated by tail pointer being set. > - */ > -static __always_inline void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - struct kmem_cache_cpu *c; > - unsigned long tid; > - void **freelist; > - > -redo: > - /* > - * Determine the currently cpus per cpu slab. > - * The cpu may change afterward. However that does not matter since > - * data is retrieved via this pointer. If we are on the same cpu > - * during the cmpxchg then the free will succeed. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* Same with comment on barrier() in slab_alloc_node() */ > - barrier(); > - > - if (unlikely(slab != c->slab)) { > - __slab_free(s, slab, head, tail_obj, cnt, addr); > - return; > - } > - > - if (USE_LOCKLESS_FAST_PATH()) { > - freelist = READ_ONCE(c->freelist); > - > - set_freepointer(s, tail_obj, freelist); > - > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - freelist, tid, > - head, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_free", s, tid); > - goto redo; > - } > - } else { > - /* Update the free list under the local lock */ > - local_lock(&s->cpu_slab->lock); > - c = this_cpu_ptr(s->cpu_slab); > - if (unlikely(slab != c->slab)) { > - local_unlock(&s->cpu_slab->lock); > - goto redo; > - } > - tid = c->tid; > - freelist = c->freelist; > - > - set_freepointer(s, tail_obj, freelist); > - c->freelist = head; > - c->tid = next_tid(tid); > - > - local_unlock(&s->cpu_slab->lock); > - } > - stat(s, FREE_FASTPATH); > -} > -#else /* CONFIG_SLUB_TINY */ > -static void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - > - __slab_free(s, slab, head, tail_obj, cnt, addr); > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static __fastpath_inline void slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, void **p, int cnt, > - unsigned long addr) > -{ > - memcg_slab_free_hook(s, slab, p, cnt); > - /* > - * With KASAN enabled slab_free_freelist_hook modifies the freelist > - * to remove objects, whose reuse must be delayed. > - */ > - if (slab_free_freelist_hook(s, &head, &tail, &cnt)) > - do_slab_free(s, slab, head, tail, cnt, addr); > -} > - > -#ifdef CONFIG_KASAN_GENERIC > -void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) > -{ > - do_slab_free(cache, virt_to_slab(x), x, NULL, 1, addr); > -} > -#endif > - > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) > -{ > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); > -} > - > -void kmem_cache_free(struct kmem_cache *s, void *x) > -{ > - s = cache_from_obj(s, x); > - if (!s) > - return; > - trace_kmem_cache_free(_RET_IP_, x, s); > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -struct detached_freelist { > - struct slab *slab; > - void *tail; > - void *freelist; > - int cnt; > - struct kmem_cache *s; > -}; > - > -/* > - * This function progressively scans the array with free objects (with > - * a limited look ahead) and extract objects belonging to the same > - * slab. It builds a detached freelist directly within the given > - * slab/objects. This can happen without any need for > - * synchronization, because the objects are owned by running process. > - * The freelist is build up as a single linked list in the objects. > - * The idea is, that this detached freelist can then be bulk > - * transferred to the real freelist(s), but only requiring a single > - * synchronization primitive. Look ahead in the array is limited due > - * to performance reasons. > - */ > -static inline > -int build_detached_freelist(struct kmem_cache *s, size_t size, > - void **p, struct detached_freelist *df) > -{ > - int lookahead = 3; > - void *object; > - struct folio *folio; > - size_t same; > - > - object = p[--size]; > - folio = virt_to_folio(object); > - if (!s) { > - /* Handle kalloc'ed objects */ > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, object); > - df->slab = NULL; > - return size; > - } > - /* Derive kmem_cache from object */ > - df->slab = folio_slab(folio); > - df->s = df->slab->slab_cache; > - } else { > - df->slab = folio_slab(folio); > - df->s = cache_from_obj(s, object); /* Support for memcg */ > - } > - > - /* Start new detached freelist */ > - df->tail = object; > - df->freelist = object; > - df->cnt = 1; > - > - if (is_kfence_address(object)) > - return size; > - > - set_freepointer(df->s, object, NULL); > - > - same = size; > - while (size) { > - object = p[--size]; > - /* df->slab is always set at this point */ > - if (df->slab == virt_to_slab(object)) { > - /* Opportunity build freelist */ > - set_freepointer(df->s, object, df->freelist); > - df->freelist = object; > - df->cnt++; > - same--; > - if (size != same) > - swap(p[size], p[same]); > - continue; > - } > - > - /* Limit look ahead search */ > - if (!--lookahead) > - break; > - } > - > - return same; > -} > - > -/* Note that interrupts must be enabled when calling this function. */ > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) > -{ > - if (!size) > - return; > - > - do { > - struct detached_freelist df; > - > - size = build_detached_freelist(s, size, p, &df); > - if (!df.slab) > - continue; > - > - slab_free(df.s, df.slab, df.freelist, df.tail, &p[size], df.cnt, > - _RET_IP_); > - } while (likely(size)); > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -#ifndef CONFIG_SLUB_TINY > -static inline int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - struct kmem_cache_cpu *c; > - unsigned long irqflags; > - int i; > - > - /* > - * Drain objects in the per cpu slab, while disabling local > - * IRQs, which protects against PREEMPT and interrupts > - * handlers invoking normal fastpath. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - object = c->freelist; > - if (unlikely(!object)) { > - /* > - * We may have removed an object from c->freelist using > - * the fastpath in the previous iteration; in that case, > - * c->tid has not been bumped yet. > - * Since ___slab_alloc() may reenable interrupts while > - * allocating memory, we should bump c->tid now. > - */ > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - > - /* > - * Invoking slow path likely have side-effect > - * of re-populating per CPU c->freelist > - */ > - p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, > - _RET_IP_, c, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - c = this_cpu_ptr(s->cpu_slab); > - maybe_wipe_obj_freeptr(s, p[i]); > - > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - continue; /* goto for-loop */ > - } > - c->freelist = get_freepointer(s, object); > - p[i] = object; > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - slub_put_cpu_ptr(s->cpu_slab); > - > - return i; > - > -error: > - slub_put_cpu_ptr(s->cpu_slab); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > - > -} > -#else /* CONFIG_SLUB_TINY */ > -static int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - int i; > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - p[i] = __slab_alloc_node(s, flags, NUMA_NO_NODE, > - _RET_IP_, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - > - return i; > - > -error: > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* Note that interrupts must be enabled when calling this function. */ > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - int i; > - struct obj_cgroup *objcg = NULL; > - > - if (!size) > - return 0; > - > - /* memcg and kmem_cache debug support */ > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (unlikely(!s)) > - return 0; > - > - i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled fastpath loop. > - */ > - if (i != 0) > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > - > -/* > - * Object placement in a slab is made very easy because we always start at > - * offset 0. If we tune the size of the object to the alignment then we can > - * get the required alignment by putting one properly sized object after > - * another. > - * > - * Notice that the allocation order determines the sizes of the per cpu > - * caches. Each processor has always one slab available for allocations. > - * Increasing the allocation order reduces the number of times that slabs > - * must be moved on and off the partial lists and is therefore a factor in > - * locking overhead. > - */ > - > -/* > - * Minimum / Maximum order of slab pages. This influences locking overhead > - * and slab fragmentation. A higher order reduces the number of partial slabs > - * and increases the number of allocations possible without having to > - * take the list_lock. > - */ > -static unsigned int slub_min_order; > -static unsigned int slub_max_order = > - IS_ENABLED(CONFIG_SLUB_TINY) ? 1 : PAGE_ALLOC_COSTLY_ORDER; > -static unsigned int slub_min_objects; > - > -/* > - * Calculate the order of allocation given an slab object size. > - * > - * The order of allocation has significant impact on performance and other > - * system components. Generally order 0 allocations should be preferred since > - * order 0 does not cause fragmentation in the page allocator. Larger objects > - * be problematic to put into order 0 slabs because there may be too much > - * unused space left. We go to a higher order if more than 1/16th of the slab > - * would be wasted. > - * > - * In order to reach satisfactory performance we must ensure that a minimum > - * number of objects is in one slab. Otherwise we may generate too much > - * activity on the partial lists which requires taking the list_lock. This is > - * less a concern for large slabs though which are rarely used. > - * > - * slub_max_order specifies the order where we begin to stop considering the > - * number of objects in a slab as critical. If we reach slub_max_order then > - * we try to keep the page order as low as possible. So we accept more waste > - * of space in favor of a small page order. > - * > - * Higher order allocations also allow the placement of more objects in a > - * slab and thereby reduce object handling overhead. If the user has > - * requested a higher minimum order then we start with that one instead of > - * the smallest order which will fit the object. > - */ > -static inline unsigned int calc_slab_order(unsigned int size, > - unsigned int min_objects, unsigned int max_order, > - unsigned int fract_leftover) > -{ > - unsigned int min_order = slub_min_order; > - unsigned int order; > - > - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) > - return get_order(size * MAX_OBJS_PER_PAGE) - 1; > - > - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); > - order <= max_order; order++) { > - > - unsigned int slab_size = (unsigned int)PAGE_SIZE << order; > - unsigned int rem; > - > - rem = slab_size % size; > - > - if (rem <= slab_size / fract_leftover) > - break; > - } > - > - return order; > -} > - > -static inline int calculate_order(unsigned int size) > -{ > - unsigned int order; > - unsigned int min_objects; > - unsigned int max_objects; > - unsigned int nr_cpus; > - > - /* > - * Attempt to find best configuration for a slab. This > - * works by first attempting to generate a layout with > - * the best configuration and backing off gradually. > - * > - * First we increase the acceptable waste in a slab. Then > - * we reduce the minimum objects required in a slab. > - */ > - min_objects = slub_min_objects; > - if (!min_objects) { > - /* > - * Some architectures will only update present cpus when > - * onlining them, so don't trust the number if it's just 1. But > - * we also don't want to use nr_cpu_ids always, as on some other > - * architectures, there can be many possible cpus, but never > - * onlined. Here we compromise between trying to avoid too high > - * order on systems that appear larger than they are, and too > - * low order on systems that appear smaller than they are. > - */ > - nr_cpus = num_present_cpus(); > - if (nr_cpus <= 1) > - nr_cpus = nr_cpu_ids; > - min_objects = 4 * (fls(nr_cpus) + 1); > - } > - max_objects = order_objects(slub_max_order, size); > - min_objects = min(min_objects, max_objects); > - > - while (min_objects > 1) { > - unsigned int fraction; > - > - fraction = 16; > - while (fraction >= 4) { > - order = calc_slab_order(size, min_objects, > - slub_max_order, fraction); > - if (order <= slub_max_order) > - return order; > - fraction /= 2; > - } > - min_objects--; > - } > - > - /* > - * We were unable to place multiple objects in a slab. Now > - * lets see if we can place a single object there. > - */ > - order = calc_slab_order(size, 1, slub_max_order, 1); > - if (order <= slub_max_order) > - return order; > - > - /* > - * Doh this slab cannot be placed using slub_max_order. > - */ > - order = calc_slab_order(size, 1, MAX_ORDER, 1); > - if (order < MAX_ORDER) > - return order; > - return -ENOSYS; > -} > - > -static void > -init_kmem_cache_node(struct kmem_cache_node *n) > -{ > - n->nr_partial = 0; > - spin_lock_init(&n->list_lock); > - INIT_LIST_HEAD(&n->partial); > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_set(&n->nr_slabs, 0); > - atomic_long_set(&n->total_objects, 0); > - INIT_LIST_HEAD(&n->full); > -#endif > -} > - > -#ifndef CONFIG_SLUB_TINY > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < > - NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * > - sizeof(struct kmem_cache_cpu)); > - > - /* > - * Must align to double word boundary for the double cmpxchg > - * instructions to work; see __pcpu_double_call_return_bool(). > - */ > - s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), > - 2 * sizeof(void *)); > - > - if (!s->cpu_slab) > - return 0; > - > - init_kmem_cache_cpus(s); > - > - return 1; > -} > -#else > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - return 1; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static struct kmem_cache *kmem_cache_node; > - > -/* > - * No kmalloc_node yet so do it by hand. We know that this is the first > - * slab on the node for this slabcache. There are no concurrent accesses > - * possible. > - * > - * Note that this function only works on the kmem_cache_node > - * when allocating for the kmem_cache_node. This is used for bootstrapping > - * memory on a fresh node that has no slab structures yet. > - */ > -static void early_kmem_cache_node_alloc(int node) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - > - BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); > - > - slab = new_slab(kmem_cache_node, GFP_NOWAIT, node); > - > - BUG_ON(!slab); > - inc_slabs_node(kmem_cache_node, slab_nid(slab), slab->objects); > - if (slab_nid(slab) != node) { > - pr_err("SLUB: Unable to allocate memory from node %d\n", node); > - pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); > - } > - > - n = slab->freelist; > - BUG_ON(!n); > -#ifdef CONFIG_SLUB_DEBUG > - init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); > - init_tracking(kmem_cache_node, n); > -#endif > - n = kasan_slab_alloc(kmem_cache_node, n, GFP_KERNEL, false); > - slab->freelist = get_freepointer(kmem_cache_node, n); > - slab->inuse = 1; > - kmem_cache_node->node[node] = n; > - init_kmem_cache_node(n); > - inc_slabs_node(kmem_cache_node, node, slab->objects); > - > - /* > - * No locks need to be taken here as it has just been > - * initialized and there is no concurrent access. > - */ > - __add_partial(n, slab, DEACTIVATE_TO_HEAD); > -} > - > -static void free_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - s->node[node] = NULL; > - kmem_cache_free(kmem_cache_node, n); > - } > -} > - > -void __kmem_cache_release(struct kmem_cache *s) > -{ > - cache_random_seq_destroy(s); > -#ifndef CONFIG_SLUB_TINY > - free_percpu(s->cpu_slab); > -#endif > - free_kmem_cache_nodes(s); > -} > - > -static int init_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - > - for_each_node_mask(node, slab_nodes) { > - struct kmem_cache_node *n; > - > - if (slab_state == DOWN) { > - early_kmem_cache_node_alloc(node); > - continue; > - } > - n = kmem_cache_alloc_node(kmem_cache_node, > - GFP_KERNEL, node); > - > - if (!n) { > - free_kmem_cache_nodes(s); > - return 0; > - } > - > - init_kmem_cache_node(n); > - s->node[node] = n; > - } > - return 1; > -} > - > -static void set_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - unsigned int nr_objects; > - > - /* > - * cpu_partial determined the maximum number of objects kept in the > - * per cpu partial lists of a processor. > - * > - * Per cpu partial lists mainly contain slabs that just have one > - * object freed. If they are used for allocation then they can be > - * filled up again with minimal effort. The slab will never hit the > - * per node partial lists and therefore no locking will be required. > - * > - * For backwards compatibility reasons, this is determined as number > - * of objects, even though we now limit maximum number of pages, see > - * slub_set_cpu_partial() > - */ > - if (!kmem_cache_has_cpu_partial(s)) > - nr_objects = 0; > - else if (s->size >= PAGE_SIZE) > - nr_objects = 6; > - else if (s->size >= 1024) > - nr_objects = 24; > - else if (s->size >= 256) > - nr_objects = 52; > - else > - nr_objects = 120; > - > - slub_set_cpu_partial(s, nr_objects); > -#endif > -} > - > -/* > - * calculate_sizes() determines the order and the distribution of data within > - * a slab object. > - */ > -static int calculate_sizes(struct kmem_cache *s) > -{ > - slab_flags_t flags = s->flags; > - unsigned int size = s->object_size; > - unsigned int order; > - > - /* > - * Round up object size to the next word boundary. We can only > - * place the free pointer at word boundaries and this determines > - * the possible location of the free pointer. > - */ > - size = ALIGN(size, sizeof(void *)); > - > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * Determine if we can poison the object itself. If the user of > - * the slab may touch the object after free or before allocation > - * then we should never poison the object itself. > - */ > - if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && > - !s->ctor) > - s->flags |= __OBJECT_POISON; > - else > - s->flags &= ~__OBJECT_POISON; > - > - > - /* > - * If we are Redzoning then check if there is some space between the > - * end of the object and the free pointer. If not then add an > - * additional word to have some bytes to store Redzone information. > - */ > - if ((flags & SLAB_RED_ZONE) && size == s->object_size) > - size += sizeof(void *); > -#endif > - > - /* > - * With that we have determined the number of bytes in actual use > - * by the object and redzoning. > - */ > - s->inuse = size; > - > - if (slub_debug_orig_size(s) || > - (flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || > - ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) || > - s->ctor) { > - /* > - * Relocate free pointer after the object if it is not > - * permitted to overwrite the first word of the object on > - * kmem_cache_free. > - * > - * This is the case if we do RCU, have a constructor or > - * destructor, are poisoning the objects, or are > - * redzoning an object smaller than sizeof(void *). > - * > - * The assumption that s->offset >= s->inuse means free > - * pointer is outside of the object is used in the > - * freeptr_outside_object() function. If that is no > - * longer true, the function needs to be modified. > - */ > - s->offset = size; > - size += sizeof(void *); > - } else { > - /* > - * Store freelist pointer near middle of object to keep > - * it away from the edges of the object to avoid small > - * sized over/underflows from neighboring allocations. > - */ > - s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *)); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_STORE_USER) { > - /* > - * Need to store information about allocs and frees after > - * the object. > - */ > - size += 2 * sizeof(struct track); > - > - /* Save the original kmalloc request size */ > - if (flags & SLAB_KMALLOC) > - size += sizeof(unsigned int); > - } > -#endif > - > - kasan_cache_create(s, &size, &s->flags); > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_RED_ZONE) { > - /* > - * Add some empty padding so that we can catch > - * overwrites from earlier objects rather than let > - * tracking information or the free pointer be > - * corrupted if a user writes before the start > - * of the object. > - */ > - size += sizeof(void *); > - > - s->red_left_pad = sizeof(void *); > - s->red_left_pad = ALIGN(s->red_left_pad, s->align); > - size += s->red_left_pad; > - } > -#endif > - > - /* > - * SLUB stores one object immediately after another beginning from > - * offset 0. In order to align the objects we have to simply size > - * each object to conform to the alignment. > - */ > - size = ALIGN(size, s->align); > - s->size = size; > - s->reciprocal_size = reciprocal_value(size); > - order = calculate_order(size); > - > - if ((int)order < 0) > - return 0; > - > - s->allocflags = 0; > - if (order) > - s->allocflags |= __GFP_COMP; > - > - if (s->flags & SLAB_CACHE_DMA) > - s->allocflags |= GFP_DMA; > - > - if (s->flags & SLAB_CACHE_DMA32) > - s->allocflags |= GFP_DMA32; > - > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - s->allocflags |= __GFP_RECLAIMABLE; > - > - /* > - * Determine the number of objects per slab > - */ > - s->oo = oo_make(order, size); > - s->min = oo_make(get_order(size), size); > - > - return !!oo_objects(s->oo); > -} > - > -static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) > -{ > - s->flags = kmem_cache_flags(s->size, flags, s->name); > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - s->random = get_random_long(); > -#endif > - > - if (!calculate_sizes(s)) > - goto error; > - if (disable_higher_order_debug) { > - /* > - * Disable debugging flags that store metadata if the min slab > - * order increased. > - */ > - if (get_order(s->size) > get_order(s->object_size)) { > - s->flags &= ~DEBUG_METADATA_FLAGS; > - s->offset = 0; > - if (!calculate_sizes(s)) > - goto error; > - } > - } > - > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) > - /* Enable fast mode */ > - s->flags |= __CMPXCHG_DOUBLE; > -#endif > - > - /* > - * The larger the object size is, the more slabs we want on the partial > - * list to avoid pounding the page allocator excessively. > - */ > - s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2); > - s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial); > - > - set_cpu_partial(s); > - > -#ifdef CONFIG_NUMA > - s->remote_node_defrag_ratio = 1000; > -#endif > - > - /* Initialize the pre-computed randomized freelist if slab is up */ > - if (slab_state >= UP) { > - if (init_cache_random_seq(s)) > - goto error; > - } > - > - if (!init_kmem_cache_nodes(s)) > - goto error; > - > - if (alloc_kmem_cache_cpus(s)) > - return 0; > - > -error: > - __kmem_cache_release(s); > - return -EINVAL; > -} > - > -static void list_slab_objects(struct kmem_cache *s, struct slab *slab, > - const char *text) > -{ > -#ifdef CONFIG_SLUB_DEBUG > - void *addr = slab_address(slab); > - void *p; > - > - slab_err(s, slab, text, s->name); > - > - spin_lock(&object_map_lock); > - __fill_map(object_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) { > - > - if (!test_bit(__obj_to_index(s, addr, p), object_map)) { > - pr_err("Object 0x%p @offset=%tu\n", p, p - addr); > - print_tracking(s, p); > - } > - } > - spin_unlock(&object_map_lock); > -#endif > -} > - > -/* > - * Attempt to free all partial slabs on a node. > - * This is called from __kmem_cache_shutdown(). We must take list_lock > - * because sysfs file might still access partial list after the shutdowning. > - */ > -static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) > -{ > - LIST_HEAD(discard); > - struct slab *slab, *h; > - > - BUG_ON(irqs_disabled()); > - spin_lock_irq(&n->list_lock); > - list_for_each_entry_safe(slab, h, &n->partial, slab_list) { > - if (!slab->inuse) { > - remove_partial(n, slab); > - list_add(&slab->slab_list, &discard); > - } else { > - list_slab_objects(s, slab, > - "Objects remaining in %s on __kmem_cache_shutdown()"); > - } > - } > - spin_unlock_irq(&n->list_lock); > - > - list_for_each_entry_safe(slab, h, &discard, slab_list) > - discard_slab(s, slab); > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (n->nr_partial || slabs_node(s, node)) > - return false; > - return true; > -} > - > -/* > - * Release all resources used by a slab cache. > - */ > -int __kmem_cache_shutdown(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - flush_all_cpus_locked(s); > - /* Attempt to free all objects */ > - for_each_kmem_cache_node(s, node, n) { > - free_partial(s, n); > - if (n->nr_partial || slabs_node(s, node)) > - return 1; > - } > - return 0; > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - void *base; > - int __maybe_unused i; > - unsigned int objnr; > - void *objp; > - void *objp0; > - struct kmem_cache *s = slab->slab_cache; > - struct track __maybe_unused *trackp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - kpp->kp_slab_cache = s; > - base = slab_address(slab); > - objp0 = kasan_reset_tag(object); > -#ifdef CONFIG_SLUB_DEBUG > - objp = restore_red_left(s, objp0); > -#else > - objp = objp0; > -#endif > - objnr = obj_to_index(s, slab, objp); > - kpp->kp_data_offset = (unsigned long)((char *)objp0 - (char *)objp); > - objp = base + s->size * objnr; > - kpp->kp_objp = objp; > - if (WARN_ON_ONCE(objp < base || objp >= base + slab->objects * s->size > - || (objp - base) % s->size) || > - !(s->flags & SLAB_STORE_USER)) > - return; > -#ifdef CONFIG_SLUB_DEBUG > - objp = fixup_red_left(s, objp); > - trackp = get_track(s, objp, TRACK_ALLOC); > - kpp->kp_ret = (void *)trackp->addr; > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries; > - > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_stack[i] = (void *)entries[i]; > - } > - > - trackp = get_track(s, objp, TRACK_FREE); > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_free_stack[i] = (void *)entries[i]; > - } > - } > -#endif > -#endif > -} > -#endif > - > -/******************************************************************** > - * Kmalloc subsystem > - *******************************************************************/ > - > -static int __init setup_slub_min_order(char *str) > -{ > - get_option(&str, (int *)&slub_min_order); > - > - return 1; > -} > - > -__setup("slub_min_order=", setup_slub_min_order); > - > -static int __init setup_slub_max_order(char *str) > -{ > - get_option(&str, (int *)&slub_max_order); > - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); > - > - return 1; > -} > - > -__setup("slub_max_order=", setup_slub_max_order); > - > -static int __init setup_slub_min_objects(char *str) > -{ > - get_option(&str, (int *)&slub_min_objects); > - > - return 1; > -} > - > -__setup("slub_min_objects=", setup_slub_min_objects); > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *s; > - unsigned int offset; > - bool is_kfence = is_kfence_address(ptr); > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find object and usable object size. */ > - s = slab->slab_cache; > - > - /* Reject impossible pointers. */ > - if (ptr < slab_address(slab)) > - usercopy_abort("SLUB object not in SLUB page?!", NULL, > - to_user, 0, n); > - > - /* Find offset within object. */ > - if (is_kfence) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = (ptr - slab_address(slab)) % s->size; > - > - /* Adjust for redzone and reject if within the redzone. */ > - if (!is_kfence && kmem_cache_debug_flags(s, SLAB_RED_ZONE)) { > - if (offset < s->red_left_pad) > - usercopy_abort("SLUB object in left red zone", > - s->name, to_user, offset, n); > - offset -= s->red_left_pad; > - } > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= s->useroffset && > - offset - s->useroffset <= s->usersize && > - n <= s->useroffset - offset + s->usersize) > - return; > - > - usercopy_abort("SLUB object", s->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > - > -#define SHRINK_PROMOTE_MAX 32 > - > -/* > - * kmem_cache_shrink discards empty slabs and promotes the slabs filled > - * up most to the head of the partial lists. New allocations will then > - * fill those up and thus they can be removed from the partial lists. > - * > - * The slabs with the least items are placed last. This results in them > - * being allocated from last increasing the chance that the last objects > - * are freed in them. > - */ > -static int __kmem_cache_do_shrink(struct kmem_cache *s) > -{ > - int node; > - int i; > - struct kmem_cache_node *n; > - struct slab *slab; > - struct slab *t; > - struct list_head discard; > - struct list_head promote[SHRINK_PROMOTE_MAX]; > - unsigned long flags; > - int ret = 0; > - > - for_each_kmem_cache_node(s, node, n) { > - INIT_LIST_HEAD(&discard); > - for (i = 0; i < SHRINK_PROMOTE_MAX; i++) > - INIT_LIST_HEAD(promote + i); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - /* > - * Build lists of slabs to discard or promote. > - * > - * Note that concurrent frees may occur while we hold the > - * list_lock. slab->inuse here is the upper limit. > - */ > - list_for_each_entry_safe(slab, t, &n->partial, slab_list) { > - int free = slab->objects - slab->inuse; > - > - /* Do not reread slab->inuse */ > - barrier(); > - > - /* We do not keep full slabs on the list */ > - BUG_ON(free <= 0); > - > - if (free == slab->objects) { > - list_move(&slab->slab_list, &discard); > - n->nr_partial--; > - dec_slabs_node(s, node, slab->objects); > - } else if (free <= SHRINK_PROMOTE_MAX) > - list_move(&slab->slab_list, promote + free - 1); > - } > - > - /* > - * Promote the slabs filled up most to the head of the > - * partial list. > - */ > - for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) > - list_splice(promote + i, &n->partial); > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - /* Release empty slabs */ > - list_for_each_entry_safe(slab, t, &discard, slab_list) > - free_slab(s, slab); > - > - if (slabs_node(s, node)) > - ret = 1; > - } > - > - return ret; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *s) > -{ > - flush_all(s); > - return __kmem_cache_do_shrink(s); > -} > - > -static int slab_mem_going_offline_callback(void *arg) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - flush_all_cpus_locked(s); > - __kmem_cache_do_shrink(s); > - } > - mutex_unlock(&slab_mutex); > - > - return 0; > -} > - > -static void slab_mem_offline_callback(void *arg) > -{ > - struct memory_notify *marg = arg; > - int offline_node; > - > - offline_node = marg->status_change_nid_normal; > - > - /* > - * If the node still has available memory. we need kmem_cache_node > - * for it yet. > - */ > - if (offline_node < 0) > - return; > - > - mutex_lock(&slab_mutex); > - node_clear(offline_node, slab_nodes); > - /* > - * We no longer free kmem_cache_node structures here, as it would be > - * racy with all get_node() users, and infeasible to protect them with > - * slab_mutex. > - */ > - mutex_unlock(&slab_mutex); > -} > - > -static int slab_mem_going_online_callback(void *arg) > -{ > - struct kmem_cache_node *n; > - struct kmem_cache *s; > - struct memory_notify *marg = arg; > - int nid = marg->status_change_nid_normal; > - int ret = 0; > - > - /* > - * If the node's memory is already available, then kmem_cache_node is > - * already created. Nothing to do. > - */ > - if (nid < 0) > - return 0; > - > - /* > - * We are bringing a node online. No memory is available yet. We must > - * allocate a kmem_cache_node structure in order to bring the node > - * online. > - */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - /* > - * The structure may already exist if the node was previously > - * onlined and offlined. > - */ > - if (get_node(s, nid)) > - continue; > - /* > - * XXX: kmem_cache_alloc_node will fallback to other nodes > - * since memory is not yet available from the node that > - * is brought up. > - */ > - n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); > - if (!n) { > - ret = -ENOMEM; > - goto out; > - } > - init_kmem_cache_node(n); > - s->node[nid] = n; > - } > - /* > - * Any cache created after this point will also have kmem_cache_node > - * initialized for the new node. > - */ > - node_set(nid, slab_nodes); > -out: > - mutex_unlock(&slab_mutex); > - return ret; > -} > - > -static int slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - int ret = 0; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - ret = slab_mem_going_online_callback(arg); > - break; > - case MEM_GOING_OFFLINE: > - ret = slab_mem_going_offline_callback(arg); > - break; > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - slab_mem_offline_callback(arg); > - break; > - case MEM_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > - if (ret) > - ret = notifier_from_errno(ret); > - else > - ret = NOTIFY_OK; > - return ret; > -} > - > -/******************************************************************** > - * Basic setup of slabs > - *******************************************************************/ > - > -/* > - * Used for early kmem_cache structures that were allocated using > - * the page allocator. Allocate them properly then fix up the pointers > - * that may be pointing to the wrong kmem_cache structure. > - */ > - > -static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) > -{ > - int node; > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - struct kmem_cache_node *n; > - > - memcpy(s, static_cache, kmem_cache->object_size); > - > - /* > - * This runs very early, and only the boot processor is supposed to be > - * up. Even if it weren't true, IRQs are not up so we couldn't fire > - * IPIs around. > - */ > - __flush_cpu_slab(s, smp_processor_id()); > - for_each_kmem_cache_node(s, node, n) { > - struct slab *p; > - > - list_for_each_entry(p, &n->partial, slab_list) > - p->slab_cache = s; > - > -#ifdef CONFIG_SLUB_DEBUG > - list_for_each_entry(p, &n->full, slab_list) > - p->slab_cache = s; > -#endif > - } > - list_add(&s->list, &slab_caches); > - return s; > -} > - > -void __init kmem_cache_init(void) > -{ > - static __initdata struct kmem_cache boot_kmem_cache, > - boot_kmem_cache_node; > - int node; > - > - if (debug_guardpage_minorder()) > - slub_max_order = 0; > - > - /* Print slub debugging pointers without hashing */ > - if (__slub_debug_enabled()) > - no_hash_pointers_enable(NULL); > - > - kmem_cache_node = &boot_kmem_cache_node; > - kmem_cache = &boot_kmem_cache; > - > - /* > - * Initialize the nodemask for which we will allocate per node > - * structures. Here we don't need taking slab_mutex yet. > - */ > - for_each_node_state(node, N_NORMAL_MEMORY) > - node_set(node, slab_nodes); > - > - create_boot_cache(kmem_cache_node, "kmem_cache_node", > - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); > - > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > - > - /* Able to allocate the per node structures */ > - slab_state = PARTIAL; > - > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - > - kmem_cache = bootstrap(&boot_kmem_cache); > - kmem_cache_node = bootstrap(&boot_kmem_cache_node); > - > - /* Now we can use the kmem_cache to allocate kmalloc slabs */ > - setup_kmalloc_cache_index_table(); > - create_kmalloc_caches(0); > - > - /* Setup random freelists for each cache */ > - init_freelist_randomization(); > - > - cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, > - slub_cpu_dead); > - > - pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%u\n", > - cache_line_size(), > - slub_min_order, slub_max_order, slub_min_objects, > - nr_cpu_ids, nr_node_ids); > -} > - > -void __init kmem_cache_init_late(void) > -{ > -#ifndef CONFIG_SLUB_TINY > - flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0); > - WARN_ON(!flushwq); > -#endif > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *s; > - > - s = find_mergeable(size, align, flags, name, ctor); > - if (s) { > - if (sysfs_slab_alias(s, name)) > - return NULL; > - > - s->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - s->object_size = max(s->object_size, size); > - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); > - } > - > - return s; > -} > - > -int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) > -{ > - int err; > - > - err = kmem_cache_open(s, flags); > - if (err) > - return err; > - > - /* Mutex is not taken during early boot */ > - if (slab_state <= UP) > - return 0; > - > - err = sysfs_slab_add(s); > - if (err) { > - __kmem_cache_release(s); > - return err; > - } > - > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > -} > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int count_inuse(struct slab *slab) > -{ > - return slab->inuse; > -} > - > -static int count_total(struct slab *slab) > -{ > - return slab->objects; > -} > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -static void validate_slab(struct kmem_cache *s, struct slab *slab, > - unsigned long *obj_map) > -{ > - void *p; > - void *addr = slab_address(slab); > - > - if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) > - return; > - > - /* Now we know that a valid freelist exists */ > - __fill_map(obj_map, s, slab); > - for_each_object(p, s, addr, slab->objects) { > - u8 val = test_bit(__obj_to_index(s, addr, p), obj_map) ? > - SLUB_RED_INACTIVE : SLUB_RED_ACTIVE; > - > - if (!check_object(s, slab, p, val)) > - break; > - } > -} > - > -static int validate_slab_node(struct kmem_cache *s, > - struct kmem_cache_node *n, unsigned long *obj_map) > -{ > - unsigned long count = 0; > - struct slab *slab; > - unsigned long flags; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - list_for_each_entry(slab, &n->partial, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != n->nr_partial) { > - pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", > - s->name, count, n->nr_partial); > - slab_add_kunit_errors(); > - } > - > - if (!(s->flags & SLAB_STORE_USER)) > - goto out; > - > - list_for_each_entry(slab, &n->full, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != atomic_long_read(&n->nr_slabs)) { > - pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", > - s->name, count, atomic_long_read(&n->nr_slabs)); > - slab_add_kunit_errors(); > - } > - > -out: > - spin_unlock_irqrestore(&n->list_lock, flags); > - return count; > -} > - > -long validate_slab_cache(struct kmem_cache *s) > -{ > - int node; > - unsigned long count = 0; > - struct kmem_cache_node *n; > - unsigned long *obj_map; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) > - return -ENOMEM; > - > - flush_all(s); > - for_each_kmem_cache_node(s, node, n) > - count += validate_slab_node(s, n, obj_map); > - > - bitmap_free(obj_map); > - > - return count; > -} > -EXPORT_SYMBOL(validate_slab_cache); > - > -#ifdef CONFIG_DEBUG_FS > -/* > - * Generate lists of code addresses where slabcache objects are allocated > - * and freed. > - */ > - > -struct location { > - depot_stack_handle_t handle; > - unsigned long count; > - unsigned long addr; > - unsigned long waste; > - long long sum_time; > - long min_time; > - long max_time; > - long min_pid; > - long max_pid; > - DECLARE_BITMAP(cpus, NR_CPUS); > - nodemask_t nodes; > -}; > - > -struct loc_track { > - unsigned long max; > - unsigned long count; > - struct location *loc; > - loff_t idx; > -}; > - > -static struct dentry *slab_debugfs_root; > - > -static void free_loc_track(struct loc_track *t) > -{ > - if (t->max) > - free_pages((unsigned long)t->loc, > - get_order(sizeof(struct location) * t->max)); > -} > - > -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) > -{ > - struct location *l; > - int order; > - > - order = get_order(sizeof(struct location) * max); > - > - l = (void *)__get_free_pages(flags, order); > - if (!l) > - return 0; > - > - if (t->count) { > - memcpy(l, t->loc, sizeof(struct location) * t->count); > - free_loc_track(t); > - } > - t->max = max; > - t->loc = l; > - return 1; > -} > - > -static int add_location(struct loc_track *t, struct kmem_cache *s, > - const struct track *track, > - unsigned int orig_size) > -{ > - long start, end, pos; > - struct location *l; > - unsigned long caddr, chandle, cwaste; > - unsigned long age = jiffies - track->when; > - depot_stack_handle_t handle = 0; > - unsigned int waste = s->object_size - orig_size; > - > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(track->handle); > -#endif > - start = -1; > - end = t->count; > - > - for ( ; ; ) { > - pos = start + (end - start + 1) / 2; > - > - /* > - * There is nothing at "end". If we end up there > - * we need to add something to before end. > - */ > - if (pos == end) > - break; > - > - l = &t->loc[pos]; > - caddr = l->addr; > - chandle = l->handle; > - cwaste = l->waste; > - if ((track->addr == caddr) && (handle == chandle) && > - (waste == cwaste)) { > - > - l->count++; > - if (track->when) { > - l->sum_time += age; > - if (age < l->min_time) > - l->min_time = age; > - if (age > l->max_time) > - l->max_time = age; > - > - if (track->pid < l->min_pid) > - l->min_pid = track->pid; > - if (track->pid > l->max_pid) > - l->max_pid = track->pid; > - > - cpumask_set_cpu(track->cpu, > - to_cpumask(l->cpus)); > - } > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > - } > - > - if (track->addr < caddr) > - end = pos; > - else if (track->addr == caddr && handle < chandle) > - end = pos; > - else if (track->addr == caddr && handle == chandle && > - waste < cwaste) > - end = pos; > - else > - start = pos; > - } > - > - /* > - * Not found. Insert new tracking element. > - */ > - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) > - return 0; > - > - l = t->loc + pos; > - if (pos < t->count) > - memmove(l + 1, l, > - (t->count - pos) * sizeof(struct location)); > - t->count++; > - l->count = 1; > - l->addr = track->addr; > - l->sum_time = age; > - l->min_time = age; > - l->max_time = age; > - l->min_pid = track->pid; > - l->max_pid = track->pid; > - l->handle = handle; > - l->waste = waste; > - cpumask_clear(to_cpumask(l->cpus)); > - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); > - nodes_clear(l->nodes); > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > -} > - > -static void process_slab(struct loc_track *t, struct kmem_cache *s, > - struct slab *slab, enum track_item alloc, > - unsigned long *obj_map) > -{ > - void *addr = slab_address(slab); > - bool is_alloc = (alloc == TRACK_ALLOC); > - void *p; > - > - __fill_map(obj_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) > - if (!test_bit(__obj_to_index(s, addr, p), obj_map)) > - add_location(t, s, get_track(s, p, alloc), > - is_alloc ? get_orig_size(s, p) : > - s->object_size); > -} > -#endif /* CONFIG_DEBUG_FS */ > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef SLAB_SUPPORTS_SYSFS > -enum slab_stat_type { > - SL_ALL, /* All slabs */ > - SL_PARTIAL, /* Only partially allocated slabs */ > - SL_CPU, /* Only slabs used for cpu caches */ > - SL_OBJECTS, /* Determine allocated objects not slabs */ > - SL_TOTAL /* Determine object capacity not slabs */ > -}; > - > -#define SO_ALL (1 << SL_ALL) > -#define SO_PARTIAL (1 << SL_PARTIAL) > -#define SO_CPU (1 << SL_CPU) > -#define SO_OBJECTS (1 << SL_OBJECTS) > -#define SO_TOTAL (1 << SL_TOTAL) > - > -static ssize_t show_slab_objects(struct kmem_cache *s, > - char *buf, unsigned long flags) > -{ > - unsigned long total = 0; > - int node; > - int x; > - unsigned long *nodes; > - int len = 0; > - > - nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); > - if (!nodes) > - return -ENOMEM; > - > - if (flags & SO_CPU) { > - int cpu; > - > - for_each_possible_cpu(cpu) { > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, > - cpu); > - int node; > - struct slab *slab; > - > - slab = READ_ONCE(c->slab); > - if (!slab) > - continue; > - > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - x = slab->objects; > - else if (flags & SO_OBJECTS) > - x = slab->inuse; > - else > - x = 1; > - > - total += x; > - nodes[node] += x; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - slab = slub_percpu_partial_read_once(c); > - if (slab) { > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - WARN_ON_ONCE(1); > - else if (flags & SO_OBJECTS) > - WARN_ON_ONCE(1); > - else > - x = slab->slabs; > - total += x; > - nodes[node] += x; > - } > -#endif > - } > - } > - > - /* > - * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex" > - * already held which will conflict with an existing lock order: > - * > - * mem_hotplug_lock->slab_mutex->kernfs_mutex > - * > - * We don't really need mem_hotplug_lock (to hold off > - * slab_mem_going_offline_callback) here because slab's memory hot > - * unplug code doesn't destroy the kmem_cache->node[] data. > - */ > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SO_ALL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - > - if (flags & SO_TOTAL) > - x = atomic_long_read(&n->total_objects); > - else if (flags & SO_OBJECTS) > - x = atomic_long_read(&n->total_objects) - > - count_partial(n, count_free); > - else > - x = atomic_long_read(&n->nr_slabs); > - total += x; > - nodes[node] += x; > - } > - > - } else > -#endif > - if (flags & SO_PARTIAL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - if (flags & SO_TOTAL) > - x = count_partial(n, count_total); > - else if (flags & SO_OBJECTS) > - x = count_partial(n, count_inuse); > - else > - x = n->nr_partial; > - total += x; > - nodes[node] += x; > - } > - } > - > - len += sysfs_emit_at(buf, len, "%lu", total); > -#ifdef CONFIG_NUMA > - for (node = 0; node < nr_node_ids; node++) { > - if (nodes[node]) > - len += sysfs_emit_at(buf, len, " N%d=%lu", > - node, nodes[node]); > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - kfree(nodes); > - > - return len; > -} > - > -#define to_slab_attr(n) container_of(n, struct slab_attribute, attr) > -#define to_slab(n) container_of(n, struct kmem_cache, kobj) > - > -struct slab_attribute { > - struct attribute attr; > - ssize_t (*show)(struct kmem_cache *s, char *buf); > - ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); > -}; > - > -#define SLAB_ATTR_RO(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RO_MODE(_name, 0400) > - > -#define SLAB_ATTR(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RW_MODE(_name, 0600) > - > -static ssize_t slab_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->size); > -} > -SLAB_ATTR_RO(slab_size); > - > -static ssize_t align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->align); > -} > -SLAB_ATTR_RO(align); > - > -static ssize_t object_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->object_size); > -} > -SLAB_ATTR_RO(object_size); > - > -static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_objects(s->oo)); > -} > -SLAB_ATTR_RO(objs_per_slab); > - > -static ssize_t order_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_order(s->oo)); > -} > -SLAB_ATTR_RO(order); > - > -static ssize_t min_partial_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%lu\n", s->min_partial); > -} > - > -static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned long min; > - int err; > - > - err = kstrtoul(buf, 10, &min); > - if (err) > - return err; > - > - s->min_partial = min; > - return length; > -} > -SLAB_ATTR(min_partial); > - > -static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - unsigned int nr_partial = 0; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - nr_partial = s->cpu_partial; > -#endif > - > - return sysfs_emit(buf, "%u\n", nr_partial); > -} > - > -static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned int objects; > - int err; > - > - err = kstrtouint(buf, 10, &objects); > - if (err) > - return err; > - if (objects && !kmem_cache_has_cpu_partial(s)) > - return -EINVAL; > - > - slub_set_cpu_partial(s, objects); > - flush_all(s); > - return length; > -} > -SLAB_ATTR(cpu_partial); > - > -static ssize_t ctor_show(struct kmem_cache *s, char *buf) > -{ > - if (!s->ctor) > - return 0; > - return sysfs_emit(buf, "%pS\n", s->ctor); > -} > -SLAB_ATTR_RO(ctor); > - > -static ssize_t aliases_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); > -} > -SLAB_ATTR_RO(aliases); > - > -static ssize_t partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL); > -} > -SLAB_ATTR_RO(partial); > - > -static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_CPU); > -} > -SLAB_ATTR_RO(cpu_slabs); > - > -static ssize_t objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects); > - > -static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects_partial); > - > -static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - int objects = 0; > - int slabs = 0; > - int cpu __maybe_unused; > - int len = 0; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - > - if (slab) > - slabs += slab->slabs; > - } > -#endif > - > - /* Approximate half-full slabs, see slub_set_cpu_partial() */ > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, "%d(%d)", objects, slabs); > - > -#if defined(CONFIG_SLUB_CPU_PARTIAL) && defined(CONFIG_SMP) > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - if (slab) { > - slabs = READ_ONCE(slab->slabs); > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, " C%d=%d(%d)", > - cpu, objects, slabs); > - } > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > -SLAB_ATTR_RO(slabs_cpu_partial); > - > -static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); > -} > -SLAB_ATTR_RO(reclaim_account); > - > -static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); > -} > -SLAB_ATTR_RO(hwcache_align); > - > -#ifdef CONFIG_ZONE_DMA > -static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); > -} > -SLAB_ATTR_RO(cache_dma); > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > -static ssize_t usersize_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->usersize); > -} > -SLAB_ATTR_RO(usersize); > -#endif > - > -static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); > -} > -SLAB_ATTR_RO(destroy_by_rcu); > - > -#ifdef CONFIG_SLUB_DEBUG > -static ssize_t slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL); > -} > -SLAB_ATTR_RO(slabs); > - > -static ssize_t total_objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); > -} > -SLAB_ATTR_RO(total_objects); > - > -static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); > -} > -SLAB_ATTR_RO(sanity_checks); > - > -static ssize_t trace_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TRACE)); > -} > -SLAB_ATTR_RO(trace); > - > -static ssize_t red_zone_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); > -} > - > -SLAB_ATTR_RO(red_zone); > - > -static ssize_t poison_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_POISON)); > -} > - > -SLAB_ATTR_RO(poison); > - > -static ssize_t store_user_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); > -} > - > -SLAB_ATTR_RO(store_user); > - > -static ssize_t validate_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t validate_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = -EINVAL; > - > - if (buf[0] == '1' && kmem_cache_debug(s)) { > - ret = validate_slab_cache(s); > - if (ret >= 0) > - ret = length; > - } > - return ret; > -} > -SLAB_ATTR(validate); > - > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef CONFIG_FAILSLAB > -static ssize_t failslab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); > -} > - > -static ssize_t failslab_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - if (s->refcount > 1) > - return -EINVAL; > - > - if (buf[0] == '1') > - WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB); > - else > - WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB); > - > - return length; > -} > -SLAB_ATTR(failslab); > -#endif > - > -static ssize_t shrink_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t shrink_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - if (buf[0] == '1') > - kmem_cache_shrink(s); > - else > - return -EINVAL; > - return length; > -} > -SLAB_ATTR(shrink); > - > -#ifdef CONFIG_NUMA > -static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->remote_node_defrag_ratio / 10); > -} > - > -static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - unsigned int ratio; > - int err; > - > - err = kstrtouint(buf, 10, &ratio); > - if (err) > - return err; > - if (ratio > 100) > - return -ERANGE; > - > - s->remote_node_defrag_ratio = ratio * 10; > - > - return length; > -} > -SLAB_ATTR(remote_node_defrag_ratio); > -#endif > - > -#ifdef CONFIG_SLUB_STATS > -static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) > -{ > - unsigned long sum = 0; > - int cpu; > - int len = 0; > - int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); > - > - if (!data) > - return -ENOMEM; > - > - for_each_online_cpu(cpu) { > - unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; > - > - data[cpu] = x; > - sum += x; > - } > - > - len += sysfs_emit_at(buf, len, "%lu", sum); > - > -#ifdef CONFIG_SMP > - for_each_online_cpu(cpu) { > - if (data[cpu]) > - len += sysfs_emit_at(buf, len, " C%d=%u", > - cpu, data[cpu]); > - } > -#endif > - kfree(data); > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > - > -static void clear_stat(struct kmem_cache *s, enum stat_item si) > -{ > - int cpu; > - > - for_each_online_cpu(cpu) > - per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; > -} > - > -#define STAT_ATTR(si, text) \ > -static ssize_t text##_show(struct kmem_cache *s, char *buf) \ > -{ \ > - return show_stat(s, buf, si); \ > -} \ > -static ssize_t text##_store(struct kmem_cache *s, \ > - const char *buf, size_t length) \ > -{ \ > - if (buf[0] != '0') \ > - return -EINVAL; \ > - clear_stat(s, si); \ > - return length; \ > -} \ > -SLAB_ATTR(text); \ > - > -STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); > -STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); > -STAT_ATTR(FREE_FASTPATH, free_fastpath); > -STAT_ATTR(FREE_SLOWPATH, free_slowpath); > -STAT_ATTR(FREE_FROZEN, free_frozen); > -STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); > -STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); > -STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); > -STAT_ATTR(ALLOC_SLAB, alloc_slab); > -STAT_ATTR(ALLOC_REFILL, alloc_refill); > -STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); > -STAT_ATTR(FREE_SLAB, free_slab); > -STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); > -STAT_ATTR(DEACTIVATE_FULL, deactivate_full); > -STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); > -STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); > -STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); > -STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); > -STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); > -STAT_ATTR(ORDER_FALLBACK, order_fallback); > -STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); > -STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); > -STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); > -STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); > -STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); > -STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); > -#endif /* CONFIG_SLUB_STATS */ > - > -#ifdef CONFIG_KFENCE > -static ssize_t skip_kfence_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_SKIP_KFENCE)); > -} > - > -static ssize_t skip_kfence_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = length; > - > - if (buf[0] == '0') > - s->flags &= ~SLAB_SKIP_KFENCE; > - else if (buf[0] == '1') > - s->flags |= SLAB_SKIP_KFENCE; > - else > - ret = -EINVAL; > - > - return ret; > -} > -SLAB_ATTR(skip_kfence); > -#endif > - > -static struct attribute *slab_attrs[] = { > - &slab_size_attr.attr, > - &object_size_attr.attr, > - &objs_per_slab_attr.attr, > - &order_attr.attr, > - &min_partial_attr.attr, > - &cpu_partial_attr.attr, > - &objects_attr.attr, > - &objects_partial_attr.attr, > - &partial_attr.attr, > - &cpu_slabs_attr.attr, > - &ctor_attr.attr, > - &aliases_attr.attr, > - &align_attr.attr, > - &hwcache_align_attr.attr, > - &reclaim_account_attr.attr, > - &destroy_by_rcu_attr.attr, > - &shrink_attr.attr, > - &slabs_cpu_partial_attr.attr, > -#ifdef CONFIG_SLUB_DEBUG > - &total_objects_attr.attr, > - &slabs_attr.attr, > - &sanity_checks_attr.attr, > - &trace_attr.attr, > - &red_zone_attr.attr, > - &poison_attr.attr, > - &store_user_attr.attr, > - &validate_attr.attr, > -#endif > -#ifdef CONFIG_ZONE_DMA > - &cache_dma_attr.attr, > -#endif > -#ifdef CONFIG_NUMA > - &remote_node_defrag_ratio_attr.attr, > -#endif > -#ifdef CONFIG_SLUB_STATS > - &alloc_fastpath_attr.attr, > - &alloc_slowpath_attr.attr, > - &free_fastpath_attr.attr, > - &free_slowpath_attr.attr, > - &free_frozen_attr.attr, > - &free_add_partial_attr.attr, > - &free_remove_partial_attr.attr, > - &alloc_from_partial_attr.attr, > - &alloc_slab_attr.attr, > - &alloc_refill_attr.attr, > - &alloc_node_mismatch_attr.attr, > - &free_slab_attr.attr, > - &cpuslab_flush_attr.attr, > - &deactivate_full_attr.attr, > - &deactivate_empty_attr.attr, > - &deactivate_to_head_attr.attr, > - &deactivate_to_tail_attr.attr, > - &deactivate_remote_frees_attr.attr, > - &deactivate_bypass_attr.attr, > - &order_fallback_attr.attr, > - &cmpxchg_double_fail_attr.attr, > - &cmpxchg_double_cpu_fail_attr.attr, > - &cpu_partial_alloc_attr.attr, > - &cpu_partial_free_attr.attr, > - &cpu_partial_node_attr.attr, > - &cpu_partial_drain_attr.attr, > -#endif > -#ifdef CONFIG_FAILSLAB > - &failslab_attr.attr, > -#endif > -#ifdef CONFIG_HARDENED_USERCOPY > - &usersize_attr.attr, > -#endif > -#ifdef CONFIG_KFENCE > - &skip_kfence_attr.attr, > -#endif > - > - NULL > -}; > - > -static const struct attribute_group slab_attr_group = { > - .attrs = slab_attrs, > -}; > - > -static ssize_t slab_attr_show(struct kobject *kobj, > - struct attribute *attr, > - char *buf) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->show) > - return -EIO; > - > - return attribute->show(s, buf); > -} > - > -static ssize_t slab_attr_store(struct kobject *kobj, > - struct attribute *attr, > - const char *buf, size_t len) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->store) > - return -EIO; > - > - return attribute->store(s, buf, len); > -} > - > -static void kmem_cache_release(struct kobject *k) > -{ > - slab_kmem_cache_release(to_slab(k)); > -} > - > -static const struct sysfs_ops slab_sysfs_ops = { > - .show = slab_attr_show, > - .store = slab_attr_store, > -}; > - > -static struct kobj_type slab_ktype = { > - .sysfs_ops = &slab_sysfs_ops, > - .release = kmem_cache_release, > -}; > - > -static struct kset *slab_kset; > - > -static inline struct kset *cache_kset(struct kmem_cache *s) > -{ > - return slab_kset; > -} > - > -#define ID_STR_LENGTH 32 > - > -/* Create a unique string id for a slab cache: > - * > - * Format :[flags-]size > - */ > -static char *create_unique_id(struct kmem_cache *s) > -{ > - char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); > - char *p = name; > - > - if (!name) > - return ERR_PTR(-ENOMEM); > - > - *p++ = ':'; > - /* > - * First flags affecting slabcache operations. We will only > - * get here for aliasable slabs so we do not need to support > - * too many flags. The flags here must cover all flags that > - * are matched during merging to guarantee that the id is > - * unique. > - */ > - if (s->flags & SLAB_CACHE_DMA) > - *p++ = 'd'; > - if (s->flags & SLAB_CACHE_DMA32) > - *p++ = 'D'; > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - *p++ = 'a'; > - if (s->flags & SLAB_CONSISTENCY_CHECKS) > - *p++ = 'F'; > - if (s->flags & SLAB_ACCOUNT) > - *p++ = 'A'; > - if (p != name + 1) > - *p++ = '-'; > - p += snprintf(p, ID_STR_LENGTH - (p - name), "%07u", s->size); > - > - if (WARN_ON(p > name + ID_STR_LENGTH - 1)) { > - kfree(name); > - return ERR_PTR(-EINVAL); > - } > - kmsan_unpoison_memory(name, p - name); > - return name; > -} > - > -static int sysfs_slab_add(struct kmem_cache *s) > -{ > - int err; > - const char *name; > - struct kset *kset = cache_kset(s); > - int unmergeable = slab_unmergeable(s); > - > - if (!unmergeable && disable_higher_order_debug && > - (slub_debug & DEBUG_METADATA_FLAGS)) > - unmergeable = 1; > - > - if (unmergeable) { > - /* > - * Slabcache can never be merged so we can use the name proper. > - * This is typically the case for debug situations. In that > - * case we can catch duplicate names easily. > - */ > - sysfs_remove_link(&slab_kset->kobj, s->name); > - name = s->name; > - } else { > - /* > - * Create a unique name for the slab as a target > - * for the symlinks. > - */ > - name = create_unique_id(s); > - if (IS_ERR(name)) > - return PTR_ERR(name); > - } > - > - s->kobj.kset = kset; > - err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); > - if (err) > - goto out; > - > - err = sysfs_create_group(&s->kobj, &slab_attr_group); > - if (err) > - goto out_del_kobj; > - > - if (!unmergeable) { > - /* Setup first alias */ > - sysfs_slab_alias(s, s->name); > - } > -out: > - if (!unmergeable) > - kfree(name); > - return err; > -out_del_kobj: > - kobject_del(&s->kobj); > - goto out; > -} > - > -void sysfs_slab_unlink(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_del(&s->kobj); > -} > - > -void sysfs_slab_release(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_put(&s->kobj); > -} > - > -/* > - * Need to buffer aliases during bootup until sysfs becomes > - * available lest we lose that information. > - */ > -struct saved_alias { > - struct kmem_cache *s; > - const char *name; > - struct saved_alias *next; > -}; > - > -static struct saved_alias *alias_list; > - > -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) > -{ > - struct saved_alias *al; > - > - if (slab_state == FULL) { > - /* > - * If we have a leftover link then remove it. > - */ > - sysfs_remove_link(&slab_kset->kobj, name); > - return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); > - } > - > - al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); > - if (!al) > - return -ENOMEM; > - > - al->s = s; > - al->name = name; > - al->next = alias_list; > - alias_list = al; > - kmsan_unpoison_memory(al, sizeof(*al)); > - return 0; > -} > - > -static int __init slab_sysfs_init(void) > -{ > - struct kmem_cache *s; > - int err; > - > - mutex_lock(&slab_mutex); > - > - slab_kset = kset_create_and_add("slab", NULL, kernel_kobj); > - if (!slab_kset) { > - mutex_unlock(&slab_mutex); > - pr_err("Cannot register slab subsystem.\n"); > - return -ENOSYS; > - } > - > - slab_state = FULL; > - > - list_for_each_entry(s, &slab_caches, list) { > - err = sysfs_slab_add(s); > - if (err) > - pr_err("SLUB: Unable to add boot slab %s to sysfs\n", > - s->name); > - } > - > - while (alias_list) { > - struct saved_alias *al = alias_list; > - > - alias_list = alias_list->next; > - err = sysfs_slab_alias(al->s, al->name); > - if (err) > - pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", > - al->name); > - kfree(al); > - } > - > - mutex_unlock(&slab_mutex); > - return 0; > -} > -late_initcall(slab_sysfs_init); > -#endif /* SLAB_SUPPORTS_SYSFS */ > - > -#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS) > -static int slab_debugfs_show(struct seq_file *seq, void *v) > -{ > - struct loc_track *t = seq->private; > - struct location *l; > - unsigned long idx; > - > - idx = (unsigned long) t->idx; > - if (idx < t->count) { > - l = &t->loc[idx]; > - > - seq_printf(seq, "%7ld ", l->count); > - > - if (l->addr) > - seq_printf(seq, "%pS", (void *)l->addr); > - else > - seq_puts(seq, "<not-available>"); > - > - if (l->waste) > - seq_printf(seq, " waste=%lu/%lu", > - l->count * l->waste, l->waste); > - > - if (l->sum_time != l->min_time) { > - seq_printf(seq, " age=%ld/%llu/%ld", > - l->min_time, div_u64(l->sum_time, l->count), > - l->max_time); > - } else > - seq_printf(seq, " age=%ld", l->min_time); > - > - if (l->min_pid != l->max_pid) > - seq_printf(seq, " pid=%ld-%ld", l->min_pid, l->max_pid); > - else > - seq_printf(seq, " pid=%ld", > - l->min_pid); > - > - if (num_online_cpus() > 1 && !cpumask_empty(to_cpumask(l->cpus))) > - seq_printf(seq, " cpus=%*pbl", > - cpumask_pr_args(to_cpumask(l->cpus))); > - > - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) > - seq_printf(seq, " nodes=%*pbl", > - nodemask_pr_args(&l->nodes)); > - > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries, j; > - > - handle = READ_ONCE(l->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - seq_puts(seq, "\n"); > - for (j = 0; j < nr_entries; j++) > - seq_printf(seq, " %pS\n", (void *)entries[j]); > - } > - } > -#endif > - seq_puts(seq, "\n"); > - } > - > - if (!idx && !t->count) > - seq_puts(seq, "No data\n"); > - > - return 0; > -} > - > -static void slab_debugfs_stop(struct seq_file *seq, void *v) > -{ > -} > - > -static void *slab_debugfs_next(struct seq_file *seq, void *v, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = ++(*ppos); > - if (*ppos <= t->count) > - return ppos; > - > - return NULL; > -} > - > -static int cmp_loc_by_count(const void *a, const void *b, const void *data) > -{ > - struct location *loc1 = (struct location *)a; > - struct location *loc2 = (struct location *)b; > - > - if (loc1->count > loc2->count) > - return -1; > - else > - return 1; > -} > - > -static void *slab_debugfs_start(struct seq_file *seq, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = *ppos; > - return ppos; > -} > - > -static const struct seq_operations slab_debugfs_sops = { > - .start = slab_debugfs_start, > - .next = slab_debugfs_next, > - .stop = slab_debugfs_stop, > - .show = slab_debugfs_show, > -}; > - > -static int slab_debug_trace_open(struct inode *inode, struct file *filep) > -{ > - > - struct kmem_cache_node *n; > - enum track_item alloc; > - int node; > - struct loc_track *t = __seq_open_private(filep, &slab_debugfs_sops, > - sizeof(struct loc_track)); > - struct kmem_cache *s = file_inode(filep)->i_private; > - unsigned long *obj_map; > - > - if (!t) > - return -ENOMEM; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) { > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0) > - alloc = TRACK_ALLOC; > - else > - alloc = TRACK_FREE; > - > - if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) { > - bitmap_free(obj_map); > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long flags; > - struct slab *slab; > - > - if (!atomic_long_read(&n->nr_slabs)) > - continue; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - list_for_each_entry(slab, &n->full, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - spin_unlock_irqrestore(&n->list_lock, flags); > - } > - > - /* Sort locations by count */ > - sort_r(t->loc, t->count, sizeof(struct location), > - cmp_loc_by_count, NULL, NULL); > - > - bitmap_free(obj_map); > - return 0; > -} > - > -static int slab_debug_trace_release(struct inode *inode, struct file *file) > -{ > - struct seq_file *seq = file->private_data; > - struct loc_track *t = seq->private; > - > - free_loc_track(t); > - return seq_release_private(inode, file); > -} > - > -static const struct file_operations slab_debugfs_fops = { > - .open = slab_debug_trace_open, > - .read = seq_read, > - .llseek = seq_lseek, > - .release = slab_debug_trace_release, > -}; > - > -static void debugfs_slab_add(struct kmem_cache *s) > -{ > - struct dentry *slab_cache_dir; > - > - if (unlikely(!slab_debugfs_root)) > - return; > - > - slab_cache_dir = debugfs_create_dir(s->name, slab_debugfs_root); > - > - debugfs_create_file("alloc_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > - > - debugfs_create_file("free_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > -} > - > -void debugfs_slab_release(struct kmem_cache *s) > -{ > - debugfs_lookup_and_remove(s->name, slab_debugfs_root); > -} > - > -static int __init slab_debugfs_init(void) > -{ > - struct kmem_cache *s; > - > - slab_debugfs_root = debugfs_create_dir("slab", NULL); > - > - list_for_each_entry(s, &slab_caches, list) > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > - > -} > -__initcall(slab_debugfs_init); > -#endif > -/* > - * The /proc/slabinfo ABI > - */ > -#ifdef CONFIG_SLUB_DEBUG > -void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) > -{ > - unsigned long nr_slabs = 0; > - unsigned long nr_objs = 0; > - unsigned long nr_free = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - nr_slabs += node_nr_slabs(n); > - nr_objs += node_nr_objs(n); > - nr_free += count_partial(n, count_free); > - } > - > - sinfo->active_objs = nr_objs - nr_free; > - sinfo->num_objs = nr_objs; > - sinfo->active_slabs = nr_slabs; > - sinfo->num_slabs = nr_slabs; > - sinfo->objects_per_slab = oo_objects(s->oo); > - sinfo->cache_order = oo_order(s->oo); > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) > -{ > -} > - > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - return -EIO; > -} > -#endif /* CONFIG_SLUB_DEBUG */
