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author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /mm/slab.h |
Initial import
Diffstat (limited to 'mm/slab.h')
-rw-r--r-- | mm/slab.h | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/mm/slab.h b/mm/slab.h new file mode 100644 index 000000000..4c3ac12dd --- /dev/null +++ b/mm/slab.h @@ -0,0 +1,380 @@ +#ifndef MM_SLAB_H +#define MM_SLAB_H +/* + * Internal slab definitions + */ + +#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 */ + +#ifdef CONFIG_SLAB +#include <linux/slab_def.h> +#endif + +#ifdef CONFIG_SLUB +#include <linux/slub_def.h> +#endif + +#include <linux/memcontrol.h> + +/* + * State of the slab allocator. + * + * This is used to describe the states of the allocator during bootup. + * Allocators use this to gradually bootstrap themselves. Most allocators + * have the problem that the structures used for managing slab caches are + * allocated from slab caches themselves. + */ +enum slab_state { + DOWN, /* No slab functionality yet */ + PARTIAL, /* SLUB: kmem_cache_node available */ + PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */ + UP, /* Slab caches usable but not all extras yet */ + FULL /* Everything is working */ +}; + +extern enum slab_state slab_state; + +/* The slab cache mutex protects the management structures during changes */ +extern struct mutex slab_mutex; + +/* The list of all slab caches on the system */ +extern struct list_head slab_caches; + +/* The slab cache that manages slab cache information */ +extern struct kmem_cache *kmem_cache; + +unsigned long calculate_alignment(unsigned long flags, + unsigned long align, unsigned long size); + +#ifndef CONFIG_SLOB +/* Kmalloc array related functions */ +void create_kmalloc_caches(unsigned long); + +/* Find the kmalloc slab corresponding for a certain size */ +struct kmem_cache *kmalloc_slab(size_t, gfp_t); +#endif + + +/* Functions provided by the slab allocators */ +extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags); + +extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size, + unsigned long flags); +extern void create_boot_cache(struct kmem_cache *, const char *name, + size_t size, unsigned long flags); + +int slab_unmergeable(struct kmem_cache *s); +struct kmem_cache *find_mergeable(size_t size, size_t align, + unsigned long flags, const char *name, void (*ctor)(void *)); +#ifndef CONFIG_SLOB +struct kmem_cache * +__kmem_cache_alias(const char *name, size_t size, size_t align, + unsigned long flags, void (*ctor)(void *)); + +unsigned long kmem_cache_flags(unsigned long object_size, + unsigned long flags, const char *name, + void (*ctor)(void *)); +#else +static inline struct kmem_cache * +__kmem_cache_alias(const char *name, size_t size, size_t align, + unsigned long flags, void (*ctor)(void *)) +{ return NULL; } + +static inline unsigned long kmem_cache_flags(unsigned long object_size, + unsigned long flags, const char *name, + void (*ctor)(void *)) +{ + return flags; +} +#endif + + +/* Legal flag mask for kmem_cache_create(), for various configurations */ +#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \ + SLAB_DESTROY_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_DEBUG_FREE) +#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_NOTRACK) +#elif defined(CONFIG_SLUB) +#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ + SLAB_TEMPORARY | SLAB_NOTRACK) +#else +#define SLAB_CACHE_FLAGS (0) +#endif + +#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) + +int __kmem_cache_shutdown(struct kmem_cache *); +int __kmem_cache_shrink(struct kmem_cache *, bool); +void slab_kmem_cache_release(struct kmem_cache *); + +struct seq_file; +struct file; + +struct slabinfo { + unsigned long active_objs; + unsigned long num_objs; + unsigned long active_slabs; + unsigned long num_slabs; + unsigned long shared_avail; + unsigned int limit; + unsigned int batchcount; + unsigned int shared; + unsigned int objects_per_slab; + unsigned int cache_order; +}; + +void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); +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); + +#ifdef CONFIG_MEMCG_KMEM +/* + * Iterate over all memcg caches of the given root cache. The caller must hold + * slab_mutex. + */ +#define for_each_memcg_cache(iter, root) \ + list_for_each_entry(iter, &(root)->memcg_params.list, \ + memcg_params.list) + +#define for_each_memcg_cache_safe(iter, tmp, root) \ + list_for_each_entry_safe(iter, tmp, &(root)->memcg_params.list, \ + memcg_params.list) + +static inline bool is_root_cache(struct kmem_cache *s) +{ + return s->memcg_params.is_root_cache; +} + +static inline bool slab_equal_or_root(struct kmem_cache *s, + struct kmem_cache *p) +{ + return p == s || p == s->memcg_params.root_cache; +} + +/* + * We use suffixes to the name in memcg because we can't have caches + * created in the system with the same name. But when we print them + * locally, better refer to them with the base name + */ +static inline const char *cache_name(struct kmem_cache *s) +{ + if (!is_root_cache(s)) + s = s->memcg_params.root_cache; + return s->name; +} + +/* + * Note, we protect with RCU only the memcg_caches array, not per-memcg caches. + * That said the caller must assure the memcg's cache won't go away by either + * taking a css reference to the owner cgroup, or holding the slab_mutex. + */ +static inline struct kmem_cache * +cache_from_memcg_idx(struct kmem_cache *s, int idx) +{ + struct kmem_cache *cachep; + struct memcg_cache_array *arr; + + rcu_read_lock(); + arr = rcu_dereference(s->memcg_params.memcg_caches); + + /* + * Make sure we will access the up-to-date value. The code updating + * memcg_caches issues a write barrier to match this (see + * memcg_create_kmem_cache()). + */ + cachep = lockless_dereference(arr->entries[idx]); + rcu_read_unlock(); + + return cachep; +} + +static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) +{ + if (is_root_cache(s)) + return s; + return s->memcg_params.root_cache; +} + +static __always_inline int memcg_charge_slab(struct kmem_cache *s, + gfp_t gfp, int order) +{ + if (!memcg_kmem_enabled()) + return 0; + if (is_root_cache(s)) + return 0; + return memcg_charge_kmem(s->memcg_params.memcg, gfp, 1 << order); +} + +static __always_inline void memcg_uncharge_slab(struct kmem_cache *s, int order) +{ + if (!memcg_kmem_enabled()) + return; + if (is_root_cache(s)) + return; + memcg_uncharge_kmem(s->memcg_params.memcg, 1 << order); +} + +extern void slab_init_memcg_params(struct kmem_cache *); + +#else /* !CONFIG_MEMCG_KMEM */ + +#define for_each_memcg_cache(iter, root) \ + for ((void)(iter), (void)(root); 0; ) +#define for_each_memcg_cache_safe(iter, tmp, root) \ + for ((void)(iter), (void)(tmp), (void)(root); 0; ) + +static inline bool is_root_cache(struct kmem_cache *s) +{ + return true; +} + +static inline bool slab_equal_or_root(struct kmem_cache *s, + struct kmem_cache *p) +{ + return true; +} + +static inline const char *cache_name(struct kmem_cache *s) +{ + return s->name; +} + +static inline struct kmem_cache * +cache_from_memcg_idx(struct kmem_cache *s, int idx) +{ + return NULL; +} + +static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) +{ + return s; +} + +static inline int memcg_charge_slab(struct kmem_cache *s, gfp_t gfp, int order) +{ + return 0; +} + +static inline void memcg_uncharge_slab(struct kmem_cache *s, int order) +{ +} + +static inline void slab_init_memcg_params(struct kmem_cache *s) +{ +} +#endif /* CONFIG_MEMCG_KMEM */ + +static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) +{ + struct kmem_cache *cachep; + struct page *page; + + /* + * When kmemcg is not being used, both assignments should return the + * same value. but we don't want to pay the assignment price in that + * case. If it is not compiled in, the compiler should be smart enough + * to not do even the assignment. In that case, slab_equal_or_root + * will also be a constant. + */ + if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE)) + return s; + + page = virt_to_head_page(x); + cachep = page->slab_cache; + if (slab_equal_or_root(cachep, s)) + return cachep; + + pr_err("%s: Wrong slab cache. %s but object is from %s\n", + __func__, cachep->name, s->name); + WARN_ON_ONCE(1); + return s; +} + +#ifndef CONFIG_SLOB +/* + * The slab lists for all objects. + */ +struct kmem_cache_node { + spinlock_t list_lock; + +#ifdef CONFIG_SLAB + struct list_head slabs_partial; /* partial list first, better asm code */ + struct list_head slabs_full; + struct list_head slabs_free; + 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 + 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 + +void *slab_start(struct seq_file *m, loff_t *pos); +void *slab_next(struct seq_file *m, void *p, loff_t *pos); +void slab_stop(struct seq_file *m, void *p); +int memcg_slab_show(struct seq_file *m, void *p); + +#endif /* MM_SLAB_H */ |