mm/slab: move struct kmem_cache_cpu declaration to slub.c

Nothing outside SLUB itself accesses the struct kmem_cache_cpu fields so
it does not need to be declared in slub_def.h. This allows also to move
enum stat_item.
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: David Rientjes <rientjes@google.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

include/linux/slub_def.h

@@ -12,60 +12,6 @@
 #include <linux/reciprocal_div.h>
 #include <linux/local_lock.h>
 
-enum stat_item {
-	ALLOC_FASTPATH,		/* Allocation from cpu slab */
-	ALLOC_SLOWPATH,		/* Allocation by getting a new cpu slab */
-	FREE_FASTPATH,		/* Free to cpu slab */
-	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 node partial list */
-	ALLOC_SLAB,		/* Cpu slab acquired from page allocator */
-	ALLOC_REFILL,		/* Refill cpu slab from slab freelist */
-	ALLOC_NODE_MISMATCH,	/* Switching cpu slab */
-	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 */
-	DEACTIVATE_BYPASS,	/* Implicit deactivation */
-	ORDER_FALLBACK,		/* Number of times fallback was necessary */
-	CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
-	CMPXCHG_DOUBLE_FAIL,	/* Number of times that cmpxchg double did not match */
-	CPU_PARTIAL_ALLOC,	/* Used cpu partial on alloc */
-	CPU_PARTIAL_FREE,	/* Refill cpu partial on free */
-	CPU_PARTIAL_NODE,	/* Refill cpu partial from node partial */
-	CPU_PARTIAL_DRAIN,	/* Drain cpu partial to node partial */
-	NR_SLUB_STAT_ITEMS
-};
-
-#ifndef CONFIG_SLUB_TINY
-/*
- * When changing the layout, make sure freelist and tid are still compatible
- * with this_cpu_cmpxchg_double() alignment requirements.
- */
-struct kmem_cache_cpu {
-	union {
-		struct {
-			void **freelist;	/* Pointer to next available object */
-			unsigned long tid;	/* Globally unique transaction id */
-		};
-		freelist_aba_t freelist_tid;
-	};
-	struct slab *slab;	/* The slab from which we are allocating */
-#ifdef CONFIG_SLUB_CPU_PARTIAL
-	struct slab *partial;	/* Partially allocated frozen slabs */
-#endif
-	local_lock_t lock;	/* Protects the fields above */
-#ifdef CONFIG_SLUB_STATS
-	unsigned stat[NR_SLUB_STAT_ITEMS];
-#endif
-};
-#endif /* CONFIG_SLUB_TINY */
-
 #ifdef CONFIG_SLUB_CPU_PARTIAL
 #define slub_percpu_partial(c)		((c)->partial)
 

mm/slub.c

@@ -330,6 +330,60 @@ static void debugfs_slab_add(struct kmem_cache *);
 static inline void debugfs_slab_add(struct kmem_cache *s) { }
 #endif
 
+enum stat_item {
+	ALLOC_FASTPATH,		/* Allocation from cpu slab */
+	ALLOC_SLOWPATH,		/* Allocation by getting a new cpu slab */
+	FREE_FASTPATH,		/* Free to cpu slab */
+	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 node partial list */
+	ALLOC_SLAB,		/* Cpu slab acquired from page allocator */
+	ALLOC_REFILL,		/* Refill cpu slab from slab freelist */
+	ALLOC_NODE_MISMATCH,	/* Switching cpu slab */
+	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 */
+	DEACTIVATE_BYPASS,	/* Implicit deactivation */
+	ORDER_FALLBACK,		/* Number of times fallback was necessary */
+	CMPXCHG_DOUBLE_CPU_FAIL,/* Failures of this_cpu_cmpxchg_double */
+	CMPXCHG_DOUBLE_FAIL,	/* Failures of slab freelist update */
+	CPU_PARTIAL_ALLOC,	/* Used cpu partial on alloc */
+	CPU_PARTIAL_FREE,	/* Refill cpu partial on free */
+	CPU_PARTIAL_NODE,	/* Refill cpu partial from node partial */
+	CPU_PARTIAL_DRAIN,	/* Drain cpu partial to node partial */
+	NR_SLUB_STAT_ITEMS
+};
+
+#ifndef CONFIG_SLUB_TINY
+/*
+ * When changing the layout, make sure freelist and tid are still compatible
+ * with this_cpu_cmpxchg_double() alignment requirements.
+ */
+struct kmem_cache_cpu {
+	union {
+		struct {
+			void **freelist;	/* Pointer to next available object */
+			unsigned long tid;	/* Globally unique transaction id */
+		};
+		freelist_aba_t freelist_tid;
+	};
+	struct slab *slab;	/* The slab from which we are allocating */
+#ifdef CONFIG_SLUB_CPU_PARTIAL
+	struct slab *partial;	/* Partially allocated frozen slabs */
+#endif
+	local_lock_t lock;	/* Protects the fields above */
+#ifdef CONFIG_SLUB_STATS
+	unsigned int stat[NR_SLUB_STAT_ITEMS];
+#endif
+};
+#endif /* CONFIG_SLUB_TINY */
+
 static inline void stat(const struct kmem_cache *s, enum stat_item si)
 {
 #ifdef CONFIG_SLUB_STATS