mm: add & use zone_end_pfn() and zone_spans_pfn()
Add 2 helpers (zone_end_pfn() and zone_spans_pfn()) to reduce code
duplication.
This also switches to using them in compaction (where an additional
variable needed to be renamed), page_alloc, vmstat, memory_hotplug, and
kmemleak.
Note that in compaction.c I avoid calling zone_end_pfn() repeatedly
because I expect at some point the sycronization issues with start_pfn &
spanned_pages will need fixing, either by actually using the seqlock or
clever memory barrier usage.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Hansen <dave@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 64c83a8..a3687af 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -250,9 +250,7 @@
do {
seq = zone_span_seqbegin(zone);
- if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
- ret = 1;
- else if (pfn < zone->zone_start_pfn)
+ if (!zone_spans_pfn(zone, pfn))
ret = 1;
} while (zone_span_seqretry(zone, seq));
@@ -990,9 +988,9 @@
end_pfn = start_pfn + pageblock_nr_pages - 1;
/* Do not cross zone boundaries */
- if (start_pfn < zone->zone_start_pfn)
+ if (!zone_spans_pfn(zone, start_pfn))
start_page = page;
- if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
+ if (!zone_spans_pfn(zone, end_pfn))
return 0;
return move_freepages(zone, start_page, end_page, migratetype);
@@ -1286,7 +1284,7 @@
spin_lock_irqsave(&zone->lock, flags);
- max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ max_zone_pfn = zone_end_pfn(zone);
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
if (pfn_valid(pfn)) {
struct page *page = pfn_to_page(pfn);
@@ -3798,7 +3796,7 @@
* the block.
*/
start_pfn = zone->zone_start_pfn;
- end_pfn = start_pfn + zone->spanned_pages;
+ end_pfn = zone_end_pfn(zone);
start_pfn = roundup(start_pfn, pageblock_nr_pages);
reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
pageblock_order;
@@ -3912,7 +3910,7 @@
* pfn out of zone.
*/
if ((z->zone_start_pfn <= pfn)
- && (pfn < z->zone_start_pfn + z->spanned_pages)
+ && (pfn < zone_end_pfn(z))
&& !(pfn & (pageblock_nr_pages - 1)))
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
@@ -4713,7 +4711,7 @@
* for the buddy allocator to function correctly.
*/
start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
- end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
+ end = pgdat_end_pfn(pgdat);
end = ALIGN(end, MAX_ORDER_NR_PAGES);
size = (end - start) * sizeof(struct page);
map = alloc_remap(pgdat->node_id, size);
@@ -5928,8 +5926,7 @@
pfn = page_to_pfn(page);
bitmap = get_pageblock_bitmap(zone, pfn);
bitidx = pfn_to_bitidx(zone, pfn);
- VM_BUG_ON(pfn < zone->zone_start_pfn);
- VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
+ VM_BUG_ON(!zone_spans_pfn(zone, pfn));
for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
if (flags & value)
@@ -6027,8 +6024,7 @@
zone = page_zone(page);
pfn = page_to_pfn(page);
- if (zone->zone_start_pfn > pfn ||
- zone->zone_start_pfn + zone->spanned_pages <= pfn)
+ if (!zone_spans_pfn(zone, pfn))
return false;
return !has_unmovable_pages(zone, page, 0, true);