---

yaml
---
r: 2850
b: refs/heads/master
c: 348f8b6
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6f167ec721108c9282d54424516a12c805e3c306
+refs/heads/master: 348f8b6c4837a07304d2f72b11ce8d96588065e0

trunk/include/linux/mm.h

@@ -395,33 +395,68 @@ static inline void put_page(struct page *page)
 /*
  * The zone field is never updated after free_area_init_core()
  * sets it, so none of the operations on it need to be atomic.
- * We'll have up to (MAX_NUMNODES * MAX_NR_ZONES) zones total,
- * so we use (MAX_NODES_SHIFT + MAX_ZONES_SHIFT) here to get enough bits.
  */
-#define NODEZONE_SHIFT (sizeof(page_flags_t)*8 - MAX_NODES_SHIFT - MAX_ZONES_SHIFT)
+
+/* Page flags: | NODE | ZONE | ... | FLAGS | */
+#define NODES_PGOFF		((sizeof(page_flags_t)*8) - NODES_SHIFT)
+#define ZONES_PGOFF		(NODES_PGOFF - ZONES_SHIFT)
+
+/*
+ * Define the bit shifts to access each section.  For non-existant
+ * sections we define the shift as 0; that plus a 0 mask ensures
+ * the compiler will optimise away reference to them.
+ */
+#define NODES_PGSHIFT		(NODES_PGOFF * (NODES_SHIFT != 0))
+#define ZONES_PGSHIFT		(ZONES_PGOFF * (ZONES_SHIFT != 0))
+
+/* NODE:ZONE is used to lookup the zone from a page. */
+#define ZONETABLE_SHIFT		(NODES_SHIFT + ZONES_SHIFT)
+#define ZONETABLE_PGSHIFT	ZONES_PGSHIFT
+
+#if NODES_SHIFT+ZONES_SHIFT > FLAGS_RESERVED
+#error NODES_SHIFT+ZONES_SHIFT > FLAGS_RESERVED
+#endif
+
 #define NODEZONE(node, zone)	((node << ZONES_SHIFT) | zone)
 
+#define ZONES_MASK		((1UL << ZONES_SHIFT) - 1)
+#define NODES_MASK		((1UL << NODES_SHIFT) - 1)
+#define ZONETABLE_MASK		((1UL << ZONETABLE_SHIFT) - 1)
+
 static inline unsigned long page_zonenum(struct page *page)
 {
-	return (page->flags >> NODEZONE_SHIFT) & (~(~0UL << ZONES_SHIFT));
+	return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
 }
 static inline unsigned long page_to_nid(struct page *page)
 {
-	return (page->flags >> (NODEZONE_SHIFT + ZONES_SHIFT));
+	return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
 }
 
 struct zone;
 extern struct zone *zone_table[];
 
 static inline struct zone *page_zone(struct page *page)
 {
-	return zone_table[page->flags >> NODEZONE_SHIFT];
+	return zone_table[(page->flags >> ZONETABLE_PGSHIFT) &
+			ZONETABLE_MASK];
+}
+
+static inline void set_page_zone(struct page *page, unsigned long zone)
+{
+	page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
+	page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
+}
+static inline void set_page_node(struct page *page, unsigned long node)
+{
+	page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
+	page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
 }
 
-static inline void set_page_zone(struct page *page, unsigned long nodezone_num)
+static inline void set_page_links(struct page *page, unsigned long zone,
+	unsigned long node)
 {
-	page->flags &= ~(~0UL << NODEZONE_SHIFT);
-	page->flags |= nodezone_num << NODEZONE_SHIFT;
+	set_page_zone(page, zone);
+	set_page_node(page, node);
 }
 
 #ifndef CONFIG_DISCONTIGMEM

trunk/include/linux/mmzone.h

@@ -414,30 +414,25 @@ extern struct pglist_data contig_page_data;
 
 #include <asm/mmzone.h>
 
+#endif /* !CONFIG_DISCONTIGMEM */
+
 #if BITS_PER_LONG == 32 || defined(ARCH_HAS_ATOMIC_UNSIGNED)
 /*
  * with 32 bit page->flags field, we reserve 8 bits for node/zone info.
  * there are 3 zones (2 bits) and this leaves 8-2=6 bits for nodes.
  */
-#define MAX_NODES_SHIFT		6
+#define FLAGS_RESERVED		8
+
 #elif BITS_PER_LONG == 64
 /*
  * with 64 bit flags field, there's plenty of room.
  */
-#define MAX_NODES_SHIFT		10
-#endif
+#define FLAGS_RESERVED		32
 
-#endif /* !CONFIG_DISCONTIGMEM */
-
-#if NODES_SHIFT > MAX_NODES_SHIFT
-#error NODES_SHIFT > MAX_NODES_SHIFT
-#endif
+#else
 
-/* There are currently 3 zones: DMA, Normal & Highmem, thus we need 2 bits */
-#define MAX_ZONES_SHIFT		2
+#error BITS_PER_LONG not defined
 
-#if ZONES_SHIFT > MAX_ZONES_SHIFT
-#error ZONES_SHIFT > MAX_ZONES_SHIFT
 #endif
 
 #endif /* !__ASSEMBLY__ */

trunk/mm/page_alloc.c

@@ -1653,7 +1653,7 @@ void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 	struct page *page;
 
 	for (page = start; page < (start + size); page++) {
-		set_page_zone(page, NODEZONE(nid, zone));
+		set_page_links(page, zone, nid);
 		set_page_count(page, 0);
 		reset_page_mapcount(page);
 		SetPageReserved(page);