[PATCH] add slab_is_available() routine for boot code

slab_is_available() indicates slab based allocators are available for use.
SPARSEMEM code needs to know this as it can be called at various times
during the boot process.

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/sparse.c b/mm/sparse.c
index d7c32de..c5e89eb 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -32,7 +32,7 @@
 	unsigned long array_size = SECTIONS_PER_ROOT *
 				   sizeof(struct mem_section);
 
-	if (system_state == SYSTEM_RUNNING)
+	if (slab_is_available())
 		section = kmalloc_node(array_size, GFP_KERNEL, nid);
 	else
 		section = alloc_bootmem_node(NODE_DATA(nid), array_size);