SLUB: Reduce memory foot print 

This reduces memory footprint by

1. Inlining small functions.

2. For the !CONFIG_SLUB_DEBUG case: Removal of u seless fields
   and functions.

Signed-off-by: Christoph Lameter <clameter@sgi.com>

---
 include/linux/slub_def.h |    4 ++++
 mm/slub.c                |   29 ++++++++++++++++++-----------
 2 files changed, 22 insertions(+), 11 deletions(-)

Index: slub/include/linux/slub_def.h
===================================================================
--- slub.orig/include/linux/slub_def.h	2007-05-23 22:34:17.000000000 -0700
+++ slub/include/linux/slub_def.h	2007-05-23 22:36:23.000000000 -0700
@@ -17,7 +17,9 @@ struct kmem_cache_node {
 	unsigned long nr_partial;
 	atomic_long_t nr_slabs;
 	struct list_head partial;
+#ifdef CONFIG_SLUB_DEBUG
 	struct list_head full;
+#endif
 };
 
 /*
@@ -45,7 +47,9 @@ struct kmem_cache {
 	int align;		/* Alignment */
 	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
 	int defrag_ratio;
Index: slub/mm/slub.c
===================================================================
--- slub.orig/mm/slub.c	2007-05-23 22:34:17.000000000 -0700
+++ slub/mm/slub.c	2007-05-23 22:36:23.000000000 -0700
@@ -254,9 +254,9 @@ static int sysfs_slab_add(struct kmem_ca
 static int sysfs_slab_alias(struct kmem_cache *, const char *);
 static void sysfs_slab_remove(struct kmem_cache *);
 #else
-static int sysfs_slab_add(struct kmem_cache *s) { return 0; }
-static int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; }
-static void sysfs_slab_remove(struct kmem_cache *s) {}
+static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
+static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; }
+static inline void sysfs_slab_remove(struct kmem_cache *s) {}
 #endif
 
 /********************************************************************
@@ -1011,7 +1011,7 @@ static struct page *allocate_slab(struct
 	return page;
 }
 
-static void setup_object(struct kmem_cache *s, struct page *page,
+static inline void setup_object(struct kmem_cache *s, struct page *page,
 				void *object)
 {
 	setup_object_debug(s, page, object);
@@ -1346,7 +1346,7 @@ static void deactivate_slab(struct kmem_
 	unfreeze_slab(s, page);
 }
 
-static void flush_slab(struct kmem_cache *s, struct page *page, int cpu)
+static inline void flush_slab(struct kmem_cache *s, struct page *page, int cpu)
 {
 	slab_lock(page);
 	deactivate_slab(s, page, cpu);
@@ -1356,7 +1356,7 @@ static void flush_slab(struct kmem_cache
  * Flush cpu slab.
  * Called from IPI handler with interrupts disabled.
  */
-static void __flush_cpu_slab(struct kmem_cache *s, int cpu)
+static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
 {
 	struct page *page = s->cpu_slab[cpu];
 
@@ -1764,7 +1764,7 @@ static inline int calculate_order(int si
 /*
  * Figure out what the alignment of the objects will be.
  */
-static unsigned long calculate_alignment(unsigned long flags,
+static inline unsigned long calculate_alignment(unsigned long flags,
 		unsigned long align, unsigned long size)
 {
 	/*
@@ -1786,13 +1786,15 @@ static unsigned long calculate_alignment
 	return ALIGN(align, sizeof(void *));
 }
 
-static void init_kmem_cache_node(struct kmem_cache_node *n)
+static inline void init_kmem_cache_node(struct kmem_cache_node *n)
 {
 	n->nr_partial = 0;
 	atomic_long_set(&n->nr_slabs, 0);
 	spin_lock_init(&n->list_lock);
 	INIT_LIST_HEAD(&n->partial);
+#ifdef CONFIG_SLUB_DEBUG
 	INIT_LIST_HEAD(&n->full);
+#endif
 }
 
 #ifdef CONFIG_NUMA
@@ -1877,11 +1879,11 @@ static int init_kmem_cache_nodes(struct 
 	return 1;
 }
 #else
-static void free_kmem_cache_nodes(struct kmem_cache *s)
+static inline void free_kmem_cache_nodes(struct kmem_cache *s)
 {
 }
 
-static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+static inline int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
 {
 	init_kmem_cache_node(&s->local_node);
 	return 1;
@@ -2278,8 +2280,9 @@ size_t ksize(const void *object)
 
 	BUG_ON(!page);
 	s = page->slab;
-	BUG_ON(!s);
 
+#ifdef CONFIG_SLUB_DEBUG
+	BUG_ON(!s);
 	/*
 	 * Debugging requires use of the padding between object
 	 * and whatever may come after it.
@@ -2295,6 +2298,8 @@ size_t ksize(const void *object)
 	if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
 		return s->inuse;
 
+#endif
+
 	/*
 	 * Else we can use all the padding etc for the allocation
 	 */
@@ -2475,10 +2480,12 @@ void __init kmem_cache_init(void)
 
 	slab_state = UP;
 
+#ifdef CONFIG_SLUB_DEBUG
 	/* Provide the correct kmalloc names now that the caches are up */
 	for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
 		kmalloc_caches[i]. name =
 			kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i);
+#endif
 
 #ifdef CONFIG_SMP
 	register_cpu_notifier(&slab_notifier);