static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
                             unsigned long end_pfn)
 {
-       unsigned long zone_start_pfn = zone->zone_start_pfn;
-       unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */
-       unsigned long zone_end_pfn = z;
        unsigned long pfn;
        int nid = zone_to_nid(zone);
 
        zone_span_writelock(zone);
-       if (zone_start_pfn == start_pfn) {
+       if (zone->zone_start_pfn == start_pfn) {
                /*
                 * If the section is smallest section in the zone, it need
                 * shrink zone->zone_start_pfn and zone->zone_spanned_pages.
                 * for shrinking zone.
                 */
                pfn = find_smallest_section_pfn(nid, zone, end_pfn,
-                                               zone_end_pfn);
+                                               zone_end_pfn(zone));
                if (pfn) {
+                       zone->spanned_pages = zone_end_pfn(zone) - pfn;
                        zone->zone_start_pfn = pfn;
-                       zone->spanned_pages = zone_end_pfn - pfn;
                } else {
                        zone->zone_start_pfn = 0;
                        zone->spanned_pages = 0;
                }
-       } else if (zone_end_pfn == end_pfn) {
+       } else if (zone_end_pfn(zone) == end_pfn) {
                /*
                 * If the section is biggest section in the zone, it need
                 * shrink zone->spanned_pages.
                 * In this case, we find second biggest valid mem_section for
                 * shrinking zone.
                 */
-               pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
+               pfn = find_biggest_section_pfn(nid, zone, zone->zone_start_pfn,
                                               start_pfn);
                if (pfn)
-                       zone->spanned_pages = pfn - zone_start_pfn + 1;
+                       zone->spanned_pages = pfn - zone->zone_start_pfn + 1;
                else {
                        zone->zone_start_pfn = 0;
                        zone->spanned_pages = 0;