[PATCH] reduce MAX_NR_ZONES: page allocator ZONE_HIGHMEM cleanup

page allocator ZONE_HIGHMEM fixups

1. We do not need to do an #ifdef in si_meminfo since both counters
   in use are zero if !CONFIG_HIGHMEM.

2. Add #ifdef in si_meminfo_node instead to avoid referencing zone
   information for ZONE_HIGHMEM if we do not have HIGHMEM
   (may not be there after the following patches).

3. Replace the use of ZONE_HIGHMEM with MAX_NR_ZONES in build_zonelists_node

4. build_zonelists_node: Remove BUG_ON for ZONE_HIGHMEM. Zone will
   be optional soon and thus BUG_ON cannot be triggered anymore.

5. init_free_area_core: Replace a use of ZONE_HIGHMEM with NR_MAX_ZONES.

[akpm@osdl.org: cleanups]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 5cde54695cfb5e02f03d87d69da1c40862c323dc..13c102b95c576f775fb0d243047a213bf6cb3082 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1199,13 +1199,8 @@ void si_meminfo(struct sysinfo *val)
        val->sharedram = 0;
        val->freeram = nr_free_pages();
        val->bufferram = nr_blockdev_pages();
-#ifdef CONFIG_HIGHMEM
        val->totalhigh = totalhigh_pages;
        val->freehigh = nr_free_highpages();
-#else
-       val->totalhigh = 0;
-       val->freehigh = 0;
-#endif
        val->mem_unit = PAGE_SIZE;
 }
 
@@ -1218,8 +1213,13 @@ void si_meminfo_node(struct sysinfo *val, int nid)
 
        val->totalram = pgdat->node_present_pages;
        val->freeram = nr_free_pages_pgdat(pgdat);
+#ifdef CONFIG_HIGHMEM
        val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
        val->freehigh = pgdat->node_zones[ZONE_HIGHMEM].free_pages;
+#else
+       val->totalhigh = 0;
+       val->freehigh = 0;
+#endif
        val->mem_unit = PAGE_SIZE;
 }
 #endif
@@ -1344,14 +1344,11 @@ static int __meminit build_zonelists_node(pg_data_t *pgdat,
 {
        struct zone *zone;
 
-       BUG_ON(zone_type > ZONE_HIGHMEM);
+       BUG_ON(zone_type >= MAX_NR_ZONES);
 
        do {
                zone = pgdat->node_zones + zone_type;
                if (populated_zone(zone)) {
-#ifndef CONFIG_HIGHMEM
-                       BUG_ON(zone_type > ZONE_NORMAL);
-#endif
                        zonelist->zones[nr_zones++] = zone;
                        check_highest_zone(zone_type);
                }
@@ -1981,7 +1978,7 @@ static void __meminit free_area_init_core(struct pglist_data *pgdat,
                if (zholes_size)
                        realsize -= zholes_size[j];
 
-               if (j < ZONE_HIGHMEM)
+               if (!is_highmem_idx(j))
                        nr_kernel_pages += realsize;
                nr_all_pages += realsize;