[PATCH] reduce MAX_NR_ZONES: make ZONE_DMA32 optional

Make ZONE_DMA32 optional

- Add #ifdefs around ZONE_DMA32 specific code and definitions.

- Add CONFIG_ZONE_DMA32 config option and use that for x86_64
  that alone needs this zone.

- Remove the use of CONFIG_DMA_IS_DMA32 and CONFIG_DMA_IS_NORMAL
  for ia64 and fix up the way per node ZVCs are calculated.

- Fall back to prior GFP_ZONEMASK of 0x03 if there is no
  DMA32 zone.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Christoph Lameter 2006-09-25 23:31:13 -07:00 committed by Linus Torvalds
parent 2f1b624868
commit fb0e7942bd
6 changed files with 25 additions and 16 deletions

View file

@ -13,7 +13,7 @@ struct vm_area_struct;
/* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low three bits) */
#define __GFP_DMA ((__force gfp_t)0x01u)
#define __GFP_HIGHMEM ((__force gfp_t)0x02u)
#ifdef CONFIG_DMA_IS_DMA32
#ifndef CONFIG_ZONE_DMA32
#define __GFP_DMA32 ((__force gfp_t)0x01) /* ZONE_DMA is ZONE_DMA32 */
#elif BITS_PER_LONG < 64
#define __GFP_DMA32 ((__force gfp_t)0x00) /* ZONE_NORMAL is ZONE_DMA32 */

View file

@ -109,12 +109,14 @@ enum zone_type {
* <16M.
*/
ZONE_DMA,
#ifdef CONFIG_ZONE_DMA32
/*
* x86_64 needs two ZONE_DMAs because it supports devices that are
* only able to do DMA to the lower 16M but also 32 bit devices that
* can only do DMA areas below 4G.
*/
ZONE_DMA32,
#endif
/*
* Normal addressable memory is in ZONE_NORMAL. DMA operations can be
* performed on pages in ZONE_NORMAL if the DMA devices support
@ -161,9 +163,13 @@ enum zone_type {
*
* NOTE! Make sure this matches the zones in <linux/gfp.h>
*/
#define GFP_ZONEMASK 0x07
/* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */
#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
#ifdef CONFIG_ZONE_DMA32
#define GFP_ZONEMASK 0x07
#else
#define GFP_ZONEMASK 0x03
#endif
struct zone {
/* Fields commonly accessed by the page allocator */
@ -429,7 +435,11 @@ static inline int is_normal(struct zone *zone)
static inline int is_dma32(struct zone *zone)
{
#ifdef CONFIG_ZONE_DMA32
return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
#else
return 0;
#endif
}
static inline int is_dma(struct zone *zone)

View file

@ -124,12 +124,10 @@ static inline unsigned long node_page_state(int node,
struct zone *zones = NODE_DATA(node)->node_zones;
return
#ifndef CONFIG_DMA_IS_NORMAL
#if !defined(CONFIG_DMA_IS_DMA32) && BITS_PER_LONG >= 64
#ifdef CONFIG_ZONE_DMA32
zone_page_state(&zones[ZONE_DMA32], item) +
#endif
zone_page_state(&zones[ZONE_NORMAL], item) +
#endif
#ifdef CONFIG_HIGHMEM
zone_page_state(&zones[ZONE_HIGHMEM], item) +
#endif