Especially, when checking for "all holes" we can avoid rechecking already processed pieces (that we are removing) - use the updated zone data instead (possibly already zero).
Cc: Andrew Morton <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Dan Williams <[email protected]> Cc: Wei Yang <[email protected]> Signed-off-by: David Hildenbrand <[email protected]> --- mm/memory_hotplug.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 0a21f6f99753..d3c34bbeb36d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -374,14 +374,11 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone, 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. @@ -389,22 +386,29 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, * 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; + } } /* @@ -413,8 +417,8 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, * change the zone. But perhaps, the zone has only hole data. Thus * it check the zone has only hole or not. */ - pfn = zone_start_pfn; - for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) { + for (pfn = zone->zone_start_pfn; + pfn < zone_end_pfn(zone); pfn += PAGES_PER_SUBSECTION) { if (unlikely(!pfn_valid(pfn))) continue; -- 2.21.0
