diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 108 |
1 files changed, 54 insertions, 54 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index 45af70315a94..8228d1276a2f 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -12,11 +12,14 @@ #ifndef _LINUX_SLAB_H #define _LINUX_SLAB_H +#include <linux/cache.h> #include <linux/gfp.h> #include <linux/overflow.h> #include <linux/types.h> #include <linux/workqueue.h> #include <linux/percpu-refcount.h> +#include <linux/cleanup.h> +#include <linux/hash.h> /* @@ -53,16 +56,18 @@ * stays valid, the trick to using this is relying on an independent * object validation pass. Something like: * - * rcu_read_lock() - * again: + * begin: + * rcu_read_lock(); * obj = lockless_lookup(key); * if (obj) { * if (!try_get_ref(obj)) // might fail for free objects - * goto again; + * rcu_read_unlock(); + * goto begin; * * if (obj->key != key) { // not the object we expected * put_ref(obj); - * goto again; + * rcu_read_unlock(); + * goto begin; * } * } * rcu_read_unlock(); @@ -106,6 +111,18 @@ /* Avoid kmemleak tracing */ #define SLAB_NOLEAKTRACE ((slab_flags_t __force)0x00800000U) +/* + * Prevent merging with compatible kmem caches. This flag should be used + * cautiously. Valid use cases: + * + * - caches created for self-tests (e.g. kunit) + * - general caches created and used by a subsystem, only when a + * (subsystem-specific) debug option is enabled + * - performance critical caches, should be very rare and consulted with slab + * maintainers, and not used together with CONFIG_SLUB_TINY + */ +#define SLAB_NO_MERGE ((slab_flags_t __force)0x01000000U) + /* Fault injection mark */ #ifdef CONFIG_FAILSLAB # define SLAB_FAILSLAB ((slab_flags_t __force)0x02000000U) @@ -167,7 +184,6 @@ struct mem_cgroup; /* * struct kmem_cache related prototypes */ -void __init kmem_cache_init(void); bool slab_is_available(void); struct kmem_cache *kmem_cache_create(const char *name, unsigned int size, @@ -212,6 +228,8 @@ void kfree(const void *objp); void kfree_sensitive(const void *objp); size_t __ksize(const void *objp); +DEFINE_FREE(kfree, void *, if (_T) kfree(_T)) + /** * ksize - Report actual allocation size of associated object * @@ -236,12 +254,17 @@ void kmem_dump_obj(void *object); * alignment larger than the alignment of a 64-bit integer. * Setting ARCH_DMA_MINALIGN in arch headers allows that. */ -#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8 +#ifdef ARCH_HAS_DMA_MINALIGN +#if ARCH_DMA_MINALIGN > 8 && !defined(ARCH_KMALLOC_MINALIGN) #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN -#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN -#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN) -#else +#endif +#endif + +#ifndef ARCH_KMALLOC_MINALIGN #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) +#elif ARCH_KMALLOC_MINALIGN > 8 +#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN +#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE) #endif /* @@ -284,7 +307,7 @@ static inline unsigned int arch_slab_minalign(void) * (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) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif @@ -292,20 +315,7 @@ static inline unsigned int arch_slab_minalign(void) #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) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif @@ -336,6 +346,12 @@ static inline unsigned int arch_slab_minalign(void) #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ (KMALLOC_MIN_SIZE) : 16) +#ifdef CONFIG_RANDOM_KMALLOC_CACHES +#define RANDOM_KMALLOC_CACHES_NR 15 // # of cache copies +#else +#define RANDOM_KMALLOC_CACHES_NR 0 +#endif + /* * Whenever changing this, take care of that kmalloc_type() and * create_kmalloc_caches() still work as intended. @@ -352,6 +368,8 @@ enum kmalloc_cache_type { #ifndef CONFIG_MEMCG_KMEM KMALLOC_CGROUP = KMALLOC_NORMAL, #endif + KMALLOC_RANDOM_START = KMALLOC_NORMAL, + KMALLOC_RANDOM_END = KMALLOC_RANDOM_START + RANDOM_KMALLOC_CACHES_NR, #ifdef CONFIG_SLUB_TINY KMALLOC_RECLAIM = KMALLOC_NORMAL, #else @@ -366,7 +384,6 @@ enum kmalloc_cache_type { NR_KMALLOC_TYPES }; -#ifndef CONFIG_SLOB extern struct kmem_cache * kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; @@ -378,14 +395,22 @@ kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; (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) +extern unsigned long random_kmalloc_seed; + +static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, unsigned long caller) { /* * 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)) +#ifdef CONFIG_RANDOM_KMALLOC_CACHES + /* RANDOM_KMALLOC_CACHES_NR (=15) copies + the KMALLOC_NORMAL */ + return KMALLOC_RANDOM_START + hash_64(caller ^ random_kmalloc_seed, + ilog2(RANDOM_KMALLOC_CACHES_NR + 1)); +#else return KMALLOC_NORMAL; +#endif /* * At least one of the flags has to be set. Their priorities in @@ -458,7 +483,6 @@ static __always_inline unsigned int __kmalloc_index(size_t size, } static_assert(PAGE_SHIFT <= 20); #define kmalloc_index(s) __kmalloc_index(s, true) -#endif /* !CONFIG_SLOB */ void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); @@ -487,10 +511,6 @@ void kmem_cache_free(struct kmem_cache *s, void *objp); void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p); int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, void **p); -/* - * Caller must not use kfree_bulk() on memory not originally allocated - * by kmalloc(), because the SLOB allocator cannot handle this. - */ static __always_inline void kfree_bulk(size_t size, void **p) { kmem_cache_free_bulk(NULL, size, p); @@ -526,7 +546,7 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align * to be at least to the size. * * The @flags argument may be one of the GFP flags defined at - * include/linux/gfp.h and described at + * include/linux/gfp_types.h and described at * :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>` * * The recommended usage of the @flags is described at @@ -567,7 +587,6 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align * Try really hard to succeed the allocation but fail * eventually. */ -#ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) { if (__builtin_constant_p(size) && size) { @@ -578,22 +597,12 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) index = kmalloc_index(size); return kmalloc_trace( - kmalloc_caches[kmalloc_type(flags)][index], + kmalloc_caches[kmalloc_type(flags, _RET_IP_)][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); -} -#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) { @@ -604,20 +613,11 @@ static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t fla index = kmalloc_index(size); return kmalloc_node_trace( - kmalloc_caches[kmalloc_type(flags)][index], + kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index], flags, node, size); } return __kmalloc_node(size, flags, node); } -#else -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) -{ - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) - return kmalloc_large_node(size, flags, node); - - return __kmalloc_node(size, flags, node); -} -#endif /** * kmalloc_array - allocate memory for an array. |