#ifndef _LINUX_SLUB_DEF_H #define _LINUX_SLUB_DEF_H /* * SLUB : A Slab allocator without object queues. * * (C) 2007 SGI, Christoph Lameter */ #include <linux/types.h> #include <linux/gfp.h> #include <linux/workqueue.h> #include <linux/kobject.h> #include <trace/kmemtrace.h> enum stat_item { ALLOC_FASTPATH, /* Allocation from cpu slab */ ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ FREE_FASTPATH, /* Free to cpu slub */ 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 partial list */ ALLOC_SLAB, /* Cpu slab acquired from page allocator */ ALLOC_REFILL, /* Refill cpu slab from slab freelist */ 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 */ ORDER_FALLBACK, /* Number of times fallback was necessary */ NR_SLUB_STAT_ITEMS }; struct kmem_cache_cpu { void **freelist; /* Pointer to first free per cpu object */ struct page *page; /* The slab from which we are allocating */ int node; /* The node of the page (or -1 for debug) */ unsigned int offset; /* Freepointer offset (in word units) */ unsigned int objsize; /* Size of an object (from kmem_cache) */ #ifdef CONFIG_SLUB_STATS unsigned stat[NR_SLUB_STAT_ITEMS]; #endif }; struct kmem_cache_node { spinlock_t list_lock; /* Protect partial list and nr_partial */ 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 }; /* * 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 long x; }; /* * Slab cache management. */ struct kmem_cache { /* Used for retriving partial slabs etc */ unsigned long flags; int size; /* The size of an object including meta data */ int objsize; /* The size of an object without meta data */ int offset; /* Free pointer offset. */ struct kmem_cache_order_objects oo; /* * Avoid an extra cache line for UP, SMP and for the node local to * struct kmem_cache. */ struct kmem_cache_node local_node; /* Allocation and freeing of slabs */ struct kmem_cache_order_objects max; 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 *); int inuse; /* Offset to metadata */ int align; /* Alignment */ unsigned long min_partial; const char *name; /* Name (only for display!) */ struct list_head list; /* List of slab caches */ #ifdef CONFIG_SLUB_DEBUG struct kobject kobj; /* For sysfs */ #endif #ifdef CONFIG_NUMA /* * Defragmentation by allocating from a remote node. */ int remote_node_defrag_ratio; struct kmem_cache_node *node[MAX_NUMNODES]; #endif #ifdef CONFIG_SMP struct kmem_cache_cpu *cpu_slab[NR_CPUS]; #else struct kmem_cache_cpu cpu_slab; #endif }; /* * Kmalloc subsystem. */ #if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8 #define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN #else #define KMALLOC_MIN_SIZE 8 #endif #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE) /* * Maximum kmalloc object size handled by SLUB. Larger object allocations * are passed through to the page allocator. The page allocator "fastpath" * is relatively slow so we need this value sufficiently high so that * performance critical objects are allocated through the SLUB fastpath. * * This should be dropped to PAGE_SIZE / 2 once the page allocator * "fastpath" becomes competitive with the slab allocator fastpaths. */ #define SLUB_MAX_SIZE (2 * PAGE_SIZE) #define SLUB_PAGE_SHIFT (PAGE_SHIFT + 2) /* * We keep the general caches in an array of slab caches that are used for * 2^x bytes of allocations. */ extern struct kmem_cache kmalloc_caches[SLUB_PAGE_SHIFT]; /* * Sorry that the following has to be that ugly but some versions of GCC * have trouble with constant propagation and loops. */ 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 <= 64 if (size > 64 && size <= 96) return 1; if (size > 128 && size <= 192) return 2; #endif 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; /* * The following is only needed to support architectures with a larger page * size than 4k. */ 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; return -1; /* * What we really wanted to do and cannot do because of compiler issues is: * int i; * for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) * if (size <= (1 << i)) * return i; */ } /* * Find the slab cache for a given combination of allocation flags and size. * * This ought to end up with a global pointer to the right cache * in kmalloc_caches. */ static __always_inline struct kmem_cache *kmalloc_slab(size_t size) { int index = kmalloc_index(size); if (index == 0) return NULL; return &kmalloc_caches[index]; } #ifdef CONFIG_ZONE_DMA #define SLUB_DMA __GFP_DMA #else /* Disable DMA functionality */ #define SLUB_DMA (__force gfp_t)0 #endif void *kmem_cache_alloc(struct kmem_cache *, gfp_t); void *__kmalloc(size_t size, gfp_t flags); #ifdef CONFIG_KMEMTRACE extern void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags); #else static __always_inline void * kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags) { return kmem_cache_alloc(s, gfpflags); } #endif static __always_inline void *kmalloc_large(size_t size, gfp_t flags) { unsigned int order = get_order(size); void *ret = (void *) __get_free_pages(flags | __GFP_COMP, order); kmemtrace_mark_alloc(KMEMTRACE_TYPE_KMALLOC, _THIS_IP_, ret, size, PAGE_SIZE << order, flags); return ret; } static __always_inline void *kmalloc(size_t size, gfp_t flags) { void *ret; if (__builtin_constant_p(size)) { if (size > SLUB_MAX_SIZE) return kmalloc_large(size, flags); if (!(flags & SLUB_DMA)) { struct kmem_cache *s = kmalloc_slab(size); if (!s) return ZERO_SIZE_PTR; ret = kmem_cache_alloc_notrace(s, flags); kmemtrace_mark_alloc(KMEMTRACE_TYPE_KMALLOC, _THIS_IP_, ret, size, s->size, flags); return ret; } } return __kmalloc(size, flags); } #ifdef CONFIG_NUMA void *__kmalloc_node(size_t size, gfp_t flags, int node); void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node); #ifdef CONFIG_KMEMTRACE extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *s, gfp_t gfpflags, int node); #else static __always_inline void * kmem_cache_alloc_node_notrace(struct kmem_cache *s, gfp_t gfpflags, int node) { return kmem_cache_alloc_node(s, gfpflags, node); } #endif static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) { void *ret; if (__builtin_constant_p(size) && size <= SLUB_MAX_SIZE && !(flags & SLUB_DMA)) { struct kmem_cache *s = kmalloc_slab(size); if (!s) return ZERO_SIZE_PTR; ret = kmem_cache_alloc_node_notrace(s, flags, node); kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_KMALLOC, _THIS_IP_, ret, size, s->size, flags, node); return ret; } return __kmalloc_node(size, flags, node); } #endif #endif /* _LINUX_SLUB_DEF_H */