[PATCH] various small cleanups

- Remove defunct active_list/inactive_list declarations (wli)

- Update an obsolete comment (wli)

- "mm/slab.c contains one leftover from the initial version with
  'unsigned short' bufctl entries.  The attached patch replaces '2'
  with the correct sizeof [which is now 4]" - Manfred Spraul

- BUG checks for vfree/vunmap being called in interrupt context
  (because they take irq-unsafe spinlocks, I guess?) - davej

- Simplify some coding in one_highpage_init() (Christoph Hellwig).

arch/i386/mm/init.c

@@ -215,19 +215,14 @@ void __init permanent_kmaps_init(pgd_t *pgd_base)
 
 void __init one_highpage_init(struct page *page, int pfn, int bad_ppro)
 {
-	if (!page_is_ram(pfn)) {
-		SetPageReserved(page);
-		return;
-	}
-	if (bad_ppro && page_kills_ppro(pfn)) {
-		SetPageReserved(page);
-		return;
-	}
+	if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) {
 		ClearPageReserved(page);
 		set_bit(PG_highmem, &page->flags);
-	atomic_set(&page->count, 1);
+		set_page_count(page, 1);
 		__free_page(page);
 		totalhigh_pages++;
+	} else
+		SetPageReserved(page);
 }
 
 #ifndef CONFIG_DISCONTIGMEM

include/linux/mm.h

@@ -19,9 +19,6 @@ extern unsigned long max_mapnr;
 extern unsigned long num_physpages;
 extern void * high_memory;
 extern int page_cluster;
-/* The inactive_clean lists are per zone. */
-extern struct list_head active_list;
-extern struct list_head inactive_list;
 
 #include <asm/page.h>
 #include <asm/pgtable.h>

include/linux/mmzone.h

@@ -151,8 +151,8 @@ struct zonelist {
  * On NUMA machines, each NUMA node would have a pg_data_t to describe
  * it's memory layout.
  *
- * XXX: we need to move the global memory statistics (active_list, ...)
- *      into the pg_data_t to properly support NUMA.
+ * Memory statistics and page replacement data structures are maintained on a
+ * per-zone basis.
  */
 struct bootmem_data;
 typedef struct pglist_data {

mm/slab.c

@@ -487,7 +487,7 @@ void __init kmem_cache_sizes_init(void)
 		/* Inc off-slab bufctl limit until the ceiling is hit. */
 		if (!(OFF_SLAB(sizes->cs_cachep))) {
 			offslab_limit = sizes->cs_size-sizeof(slab_t);
-			offslab_limit /= 2;
+			offslab_limit /= sizeof(kmem_bufctl_t);
 		}
 		sizes->cs_dmacachep = kmem_cache_create(
 		    cache_names[sizes-cache_sizes].name_dma, 

mm/vmalloc.c

@@ -11,6 +11,8 @@
 #include <linux/highmem.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/interrupt.h>
+
 #include <linux/vmalloc.h>
 
 #include <asm/uaccess.h>
@@ -309,6 +311,7 @@ void __vunmap(void *addr, int deallocate_pages)
  */
 void vfree(void *addr)
 {
+	BUG_ON(in_interrupt());
 	__vunmap(addr, 1);
 }
 
@@ -324,6 +327,7 @@ void vfree(void *addr)
  */
 void vunmap(void *addr)
 {
+	BUG_ON(in_interrupt());
 	__vunmap(addr, 0);
 }