From 950b68d9178b6209e92461ec371eee81f0f20190 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 3 Feb 2020 17:34:16 -0800 Subject: mm/memory_hotplug: don't check for "all holes" in shrink_zone_span() If we have holes, the holes will automatically get detected and removed once we remove the next bigger/smaller section. The extra checks can go. Link: http://lkml.kernel.org/r/20191006085646.5768-9-david@redhat.com Signed-off-by: David Hildenbrand Cc: Michal Hocko Cc: "Matthew Wilcox (Oracle)" Cc: "Aneesh Kumar K.V" Cc: Pavel Tatashin Cc: Greg Kroah-Hartman Cc: Dan Williams Cc: Logan Gunthorpe Cc: Oscar Salvador Cc: Pankaj Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory_hotplug.c | 34 +++++++--------------------------- 1 file changed, 7 insertions(+), 27 deletions(-) (limited to 'mm') diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 77cb164a2d96..61bd62d15fff 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -411,6 +411,9 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, if (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) { /* @@ -423,34 +426,11 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, start_pfn); if (pfn) zone->spanned_pages = pfn - zone_start_pfn + 1; + else { + zone->zone_start_pfn = 0; + zone->spanned_pages = 0; + } } - - /* - * The section is not biggest or smallest mem_section in the zone, it - * only creates a hole in the zone. So in this case, we need not - * 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) { - if (unlikely(!pfn_to_online_page(pfn))) - continue; - - if (page_zone(pfn_to_page(pfn)) != zone) - continue; - - /* Skip range to be removed */ - if (pfn >= start_pfn && pfn < end_pfn) - continue; - - /* If we find valid section, we have nothing to do */ - zone_span_writeunlock(zone); - return; - } - - /* The zone has no valid section */ - zone->zone_start_pfn = 0; - zone->spanned_pages = 0; zone_span_writeunlock(zone); } -- cgit v1.2.3