EVOLUTION-MANAGER

Edit File: slab.h

/* * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk). * * (C) SGI 2006, Christoph Lameter * Cleaned up and restructured to ease the addition of alternative * implementations of SLAB allocators. */ #ifndef _LINUX_SLAB_H #define _LINUX_SLAB_H #include <linux/gfp.h> #include <linux/overflow.h> #include <linux/types.h> #include <linux/workqueue.h> /* * Flags to pass to kmem_cache_create(). * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set. */ #define SLAB_CONSISTENCY_CHECKS 0x00000100UL /* DEBUG: Perform (expensive) checks on alloc/free */ #define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */ #define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */ #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */ #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */ #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */ #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */ /* * SLAB_DESTROY_BY_RCU - **WARNING** READ THIS! * * This delays freeing the SLAB page by a grace period, it does _NOT_ * delay object freeing. This means that if you do kmem_cache_free() * that memory location is free to be reused at any time. Thus it may * be possible to see another object there in the same RCU grace period. * * This feature only ensures the memory location backing the object * stays valid, the trick to using this is relying on an independent * object validation pass. Something like: * * rcu_read_lock() * again: * obj = lockless_lookup(key); * if (obj) { * if (!try_get_ref(obj)) // might fail for free objects * goto again; * * if (obj->key != key) { // not the object we expected * put_ref(obj); * goto again; * } * } * rcu_read_unlock(); * * See also the comment on struct slab_rcu in mm/slab.c. */ #define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */ #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */ #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */ /* Flag to prevent checks on free */ #ifdef CONFIG_DEBUG_OBJECTS # define SLAB_DEBUG_OBJECTS 0x00400000UL #else # define SLAB_DEBUG_OBJECTS 0x00000000UL #endif #define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */ /* Don't track use of uninitialized memory */ #ifdef CONFIG_KMEMCHECK # define SLAB_NOTRACK 0x01000000UL #else # define SLAB_NOTRACK 0x00000000UL #endif #ifdef CONFIG_FAILSLAB # define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */ #else # define SLAB_FAILSLAB 0x00000000UL #endif #ifdef CONFIG_MEMCG_KMEM # define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */ #else # define SLAB_ACCOUNT 0x00000000UL #endif /* The following flags affect the page allocator grouping pages by mobility */ #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ /* * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. * * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault. * * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can. * Both make kfree a no-op. */ #define ZERO_SIZE_PTR ((void *)16) #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \ (unsigned long)ZERO_SIZE_PTR) struct mem_cgroup; /* * struct kmem_cache related prototypes */ void __init kmem_cache_init(void); int slab_is_available(void); struct kmem_cache *kmem_cache_create(const char *, size_t, size_t, unsigned long, void (*)(void *)); #ifdef CONFIG_MEMCG_KMEM struct kmem_cache *kmem_cache_create_memcg(struct mem_cgroup *, struct kmem_cache *); void __kmemcg_cache_deactivate(struct kmem_cache *s); #endif void kmem_cache_destroy(struct kmem_cache *); int kmem_cache_shrink(struct kmem_cache *); void kmem_cache_free(struct kmem_cache *, void *); /* * Please use this macro to create slab caches. Simply specify the * name of the structure and maybe some flags that are listed above. * * The alignment of the struct determines object alignment. If you * f.e. add ____cacheline_aligned_in_smp to the struct declaration * then the objects will be properly aligned in SMP configurations. */ #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\ sizeof(struct __struct), __alignof__(struct __struct),\ (__flags), NULL) /* * Common kmalloc functions provided by all allocators */ void * __must_check __krealloc(const void *, size_t, gfp_t); void * __must_check krealloc(const void *, size_t, gfp_t); void kfree(const void *); void kzfree(const void *); size_t ksize(const void *); #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR const char *__check_heap_object(const void *ptr, unsigned long n, struct page *page); #else static inline const char *__check_heap_object(const void *ptr, unsigned long n, struct page *page) { return NULL; } #endif /* * Some archs want to perform DMA into kmalloc caches and need a guaranteed * alignment larger than the alignment of a 64-bit integer. * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that. */ #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN) #else #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) #endif #ifdef CONFIG_SLOB /* * Common fields provided in kmem_cache by all slab allocators * This struct is either used directly by the allocator (SLOB) * or the allocator must include definitions for all fields * provided in kmem_cache_common in their definition of kmem_cache. * * Once we can do anonymous structs (C11 standard) we could put a * anonymous struct definition in these allocators so that the * separate allocations in the kmem_cache structure of SLAB and * SLUB is no longer needed. */ struct kmem_cache { unsigned int object_size;/* The original size of the object */ unsigned int size; /* The aligned/padded/added on size */ unsigned int align; /* Alignment as calculated */ unsigned long flags; /* Active flags on the slab */ const char *name; /* Slab name for sysfs */ int refcount; /* Use counter */ void (*ctor)(void *); /* Called on object slot creation */ struct list_head list; /* List of all slab caches on the system */ }; #endif /* CONFIG_SLOB */ /* * Kmalloc array related definitions */ #ifdef CONFIG_SLAB /* * The largest kmalloc size supported by the SLAB allocators is * 32 megabyte (2^25) or the maximum allocatable page order if that is * less than 32 MB. * * WARNING: Its not easy to increase this value since the allocators have * to do various tricks to work around compiler limitations in order to * ensure proper constant folding. */ #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ (MAX_ORDER + PAGE_SHIFT - 1) : 25) #define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif #endif #ifdef CONFIG_SLUB /* * 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 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) /* Maximum size for which we actually use a slab cache */ #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH) /* Maximum order allocatable via the slab allocagtor */ #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT) /* * Kmalloc subsystem. */ #ifndef KMALLOC_MIN_SIZE #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) #endif #ifndef CONFIG_SLOB extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1]; #ifdef CONFIG_ZONE_DMA extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1]; #endif /* * Figure out which kmalloc slab an allocation of a certain size * belongs to. * 0 = zero alloc * 1 = 65 .. 96 bytes * 2 = 120 .. 192 bytes * n = 2^(n-1) .. 2^n -1 */ static __always_inline int kmalloc_index(size_t size) { 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 (size <= 4 * 1024 * 1024) return 22; if (size <= 8 * 1024 * 1024) return 23; if (size <= 16 * 1024 * 1024) return 24; if (size <= 32 * 1024 * 1024) return 25; if (size <= 64 * 1024 * 1024) return 26; BUG(); /* Will never be reached. Needed because the compiler may complain */ return -1; } #endif /* !CONFIG_SLOB */ #ifdef CONFIG_SLAB #include <linux/slab_def.h> #endif #ifdef CONFIG_SLUB #include <linux/slub_def.h> #endif #ifdef CONFIG_SLOB #include <linux/slob_def.h> #endif /* * Determine size used for the nth kmalloc cache. * return size or 0 if a kmalloc cache for that * size does not exist */ static __always_inline int kmalloc_size(int n) { #ifndef CONFIG_SLOB if (n > 2) return 1 << n; if (n == 1 && KMALLOC_MIN_SIZE <= 32) return 96; if (n == 2 && KMALLOC_MIN_SIZE <= 64) return 192; #endif return 0; } /* * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment. * Intended for arches that get misalignment faults even for 64 bit integer * aligned buffers. */ #ifndef ARCH_SLAB_MINALIGN #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long) #endif /* * This is the main placeholder for memcg-related information in kmem caches. * struct kmem_cache will hold a pointer to it, so the memory cost while * disabled is 1 pointer. The runtime cost while enabled, gets bigger than it * would otherwise be if that would be bundled in kmem_cache: we'll need an * extra pointer chase. But the trade off clearly lays in favor of not * penalizing non-users. * * Both the root cache and the child caches will have it. For the root cache, * this will hold a dynamically allocated array large enough to hold * information about the currently limited memcgs in the system. To allow the * array to be accessed without taking any locks, on relocation we free the old * version only after a grace period. * * Child caches will hold extra metadata needed for its operation. Fields are: * * @memcg: pointer to the memcg this cache belongs to * @list: list_head for the list of all caches in this memcg * @root_cache: pointer to the global, root cache, this cache was derived from * @nr_pages: number of pages that belongs to this cache. */ struct memcg_cache_params { bool is_root_cache; union { #ifdef __GENKSYMS__ struct kmem_cache *memcg_caches[0]; #else struct { struct kmem_cache *memcg_caches[0]; struct rcu_head rcu_head; }; #endif struct { struct mem_cgroup *memcg; struct list_head list; struct kmem_cache *root_cache; RH_KABI_DEPRECATE(bool, dead) atomic_t nr_pages; RH_KABI_DEPRECATE(struct work_struct, destroy) }; }; }; int memcg_update_all_caches(int num_memcgs); struct seq_file; int cache_show(struct kmem_cache *s, struct seq_file *m); void print_slabinfo_header(struct seq_file *m); /** * kmalloc_array - allocate memory for an array. * @n: number of elements. * @size: element size. * @flags: the type of memory to allocate. * * The @flags argument may be one of: * * %GFP_USER - Allocate memory on behalf of user. May sleep. * * %GFP_KERNEL - Allocate normal kernel ram. May sleep. * * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools. * For example, use this inside interrupt handlers. * * %GFP_HIGHUSER - Allocate pages from high memory. * * %GFP_NOIO - Do not do any I/O at all while trying to get memory. * * %GFP_NOFS - Do not make any fs calls while trying to get memory. * * %GFP_NOWAIT - Allocation will not sleep. * * %__GFP_THISNODE - Allocate node-local memory only. * * %GFP_DMA - Allocation suitable for DMA. * Should only be used for kmalloc() caches. Otherwise, use a * slab created with SLAB_DMA. * * Also it is possible to set different flags by OR'ing * in one or more of the following additional @flags: * * %__GFP_COLD - Request cache-cold pages instead of * trying to return cache-warm pages. * * %__GFP_HIGH - This allocation has high priority and may use emergency pools. * * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail * (think twice before using). * * %__GFP_NORETRY - If memory is not immediately available, * then give up at once. * * %__GFP_NOWARN - If allocation fails, don't issue any warnings. * * %__GFP_REPEAT - If allocation fails initially, try once more before failing. * * There are other flags available as well, but these are not intended * for general use, and so are not documented here. For a full list of * potential flags, always refer to linux/gfp.h. */ static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags) { size_t bytes; if (unlikely(check_mul_overflow(n, size, &bytes))) return NULL; if (__builtin_constant_p(n) && __builtin_constant_p(size)) return kmalloc(bytes, flags); return __kmalloc(bytes, flags); } /** * kcalloc - allocate memory for an array. The memory is set to zero. * @n: number of elements. * @size: element size. * @flags: the type of memory to allocate (see kmalloc). */ static inline void *kcalloc(size_t n, size_t size, gfp_t flags) { return kmalloc_array(n, size, flags | __GFP_ZERO); } /* * Bulk allocation and freeing operations. These are accellerated in an * allocator specific way to avoid taking locks repeatedly or building * metadata structures unnecessarily. * * Note that interrupts must be enabled when calling these functions. */ void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **); #if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB) /** * kmalloc_node - allocate memory from a specific node * @size: how many bytes of memory are required. * @flags: the type of memory to allocate (see kcalloc). * @node: node to allocate from. * * kmalloc() for non-local nodes, used to allocate from a specific node * if available. Equivalent to kmalloc() in the non-NUMA single-node * case. */ static inline void *kmalloc_node(size_t size, gfp_t flags, int node) { return kmalloc(size, flags); } static inline void *__kmalloc_node(size_t size, gfp_t flags, int node) { return __kmalloc(size, flags); } void *kmem_cache_alloc(struct kmem_cache *, gfp_t); static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int node) { return kmem_cache_alloc(cachep, flags); } #endif /* !CONFIG_NUMA && !CONFIG_SLOB */ /* * kmalloc_track_caller is a special version of kmalloc that records the * calling function of the routine calling it for slab leak tracking instead * of just the calling function (confusing, eh?). * It's useful when the call to kmalloc comes from a widely-used standard * allocator where we care about the real place the memory allocation * request comes from. */ #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \ (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \ (defined(CONFIG_SLOB) && defined(CONFIG_TRACING)) extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long); #define kmalloc_track_caller(size, flags) \ __kmalloc_track_caller(size, flags, _RET_IP_) #else #define kmalloc_track_caller(size, flags) \ __kmalloc(size, flags) #endif /* DEBUG_SLAB */ static inline void *kmalloc_array_node(size_t n, size_t size, gfp_t flags, int node) { size_t bytes; if (unlikely(check_mul_overflow(n, size, &bytes))) return NULL; if (__builtin_constant_p(n) && __builtin_constant_p(size)) return kmalloc_node(bytes, flags, node); return __kmalloc_node(bytes, flags, node); } static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node) { return kmalloc_array_node(n, size, flags | __GFP_ZERO, node); } #ifdef CONFIG_NUMA /* * kmalloc_node_track_caller is a special version of kmalloc_node that * records the calling function of the routine calling it for slab leak * tracking instead of just the calling function (confusing, eh?). * It's useful when the call to kmalloc_node comes from a widely-used * standard allocator where we care about the real place the memory * allocation request comes from. */ #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \ (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \ (defined(CONFIG_SLOB) && defined(CONFIG_TRACING)) extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long); #define kmalloc_node_track_caller(size, flags, node) \ __kmalloc_node_track_caller(size, flags, node, \ _RET_IP_) #else #define kmalloc_node_track_caller(size, flags, node) \ __kmalloc_node(size, flags, node) #endif #else /* CONFIG_NUMA */ #define kmalloc_node_track_caller(size, flags, node) \ kmalloc_track_caller(size, flags) #endif /* CONFIG_NUMA */ /* * Shortcuts */ static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags) { return kmem_cache_alloc(k, flags | __GFP_ZERO); } /** * kzalloc - allocate memory. The memory is set to zero. * @size: how many bytes of memory are required. * @flags: the type of memory to allocate (see kmalloc). */ static inline void *kzalloc(size_t size, gfp_t flags) { return kmalloc(size, flags | __GFP_ZERO); } /** * kzalloc_node - allocate zeroed memory from a particular memory node. * @size: how many bytes of memory are required. * @flags: the type of memory to allocate (see kmalloc). * @node: memory node from which to allocate */ static inline void *kzalloc_node(size_t size, gfp_t flags, int node) { return kmalloc_node(size, flags | __GFP_ZERO, node); } /* * Determine the size of a slab object */ static inline unsigned int kmem_cache_size(struct kmem_cache *s) { return s->object_size; } void __init kmem_cache_init_late(void); #endif /* _LINUX_SLAB_H */