bootmem: Reimplement __absent_pages_in_range() using for_each_mem_pfn_range()
__absent_pages_in_range() was needlessly complex. Reimplement it
using for_each_mem_pfn_range().
Also, update zone_absent_pages_in_node() such that it doesn't call
__absent_pages_in_range() with @zone_start_pfn which is larger than
@zone_end_pfn.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310460395-30913-3-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 69fffab..3092a97 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4044,46 +4044,16 @@
unsigned long range_start_pfn,
unsigned long range_end_pfn)
{
- int i = 0;
- unsigned long prev_end_pfn = 0, hole_pages = 0;
- unsigned long start_pfn;
+ unsigned long nr_absent = range_end_pfn - range_start_pfn;
+ unsigned long start_pfn, end_pfn;
+ int i;
- /* Find the end_pfn of the first active range of pfns in the node */
- i = first_active_region_index_in_nid(nid);
- if (i == -1)
- return 0;
-
- prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
-
- /* Account for ranges before physical memory on this node */
- if (early_node_map[i].start_pfn > range_start_pfn)
- hole_pages = prev_end_pfn - range_start_pfn;
-
- /* Find all holes for the zone within the node */
- for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
-
- /* No need to continue if prev_end_pfn is outside the zone */
- if (prev_end_pfn >= range_end_pfn)
- break;
-
- /* Make sure the end of the zone is not within the hole */
- start_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
- prev_end_pfn = max(prev_end_pfn, range_start_pfn);
-
- /* Update the hole size cound and move on */
- if (start_pfn > range_start_pfn) {
- BUG_ON(prev_end_pfn > start_pfn);
- hole_pages += start_pfn - prev_end_pfn;
- }
- prev_end_pfn = early_node_map[i].end_pfn;
+ for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
+ start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
+ end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
+ nr_absent -= end_pfn - start_pfn;
}
-
- /* Account for ranges past physical memory on this node */
- if (range_end_pfn > prev_end_pfn)
- hole_pages += range_end_pfn -
- max(range_start_pfn, prev_end_pfn);
-
- return hole_pages;
+ return nr_absent;
}
/**
@@ -4104,14 +4074,14 @@
unsigned long zone_type,
unsigned long *ignored)
{
+ unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
+ unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
unsigned long node_start_pfn, node_end_pfn;
unsigned long zone_start_pfn, zone_end_pfn;
get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
- zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type],
- node_start_pfn);
- zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
- node_end_pfn);
+ zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
+ zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
adjust_zone_range_for_zone_movable(nid, zone_type,
node_start_pfn, node_end_pfn,