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 */