[PATCH v9 3/8] mm,memory_hotplug: Factor out adjusting present pages into adjust_present_page_count()

[Oscar Salvador]

From: David Hildenbrand <da...@redhat.com>

Let's have a single place (inspired by adjust_managed_page_count()) where
we adjust present pages.
In contrast to adjust_managed_page_count(), only memory onlining/offlining
is allowed to modify the number of present pages.

Signed-off-by: David Hildenbrand <da...@redhat.com>
Signed-off-by: Oscar Salvador <osalva...@suse.de>
Reviewed-by: Oscar Salvador <osalva...@suse.de>
---
 mm/memory_hotplug.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 25e59d5dc13c..d05056b3c173 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -829,6 +829,16 @@ struct zone * zone_for_pfn_range(int online_type, int nid, 
unsigned start_pfn,
        return default_zone_for_pfn(nid, start_pfn, nr_pages);
 }
 
+static void adjust_present_page_count(struct zone *zone, long nr_pages)
+{
+       unsigned long flags;
+
+       zone->present_pages += nr_pages;
+       pgdat_resize_lock(zone->zone_pgdat, &flags);
+       zone->zone_pgdat->node_present_pages += nr_pages;
+       pgdat_resize_unlock(zone->zone_pgdat, &flags);
+}
+
 int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
                       int online_type, int nid)
 {
@@ -882,11 +892,7 @@ int __ref online_pages(unsigned long pfn, unsigned long 
nr_pages,
        }
 
        online_pages_range(pfn, nr_pages);
-       zone->present_pages += nr_pages;
-
-       pgdat_resize_lock(zone->zone_pgdat, &flags);
-       zone->zone_pgdat->node_present_pages += nr_pages;
-       pgdat_resize_unlock(zone->zone_pgdat, &flags);
+       adjust_present_page_count(zone, nr_pages);
 
        node_states_set_node(nid, &arg);
        if (need_zonelists_rebuild)
@@ -1701,11 +1707,7 @@ int __ref offline_pages(unsigned long start_pfn, 
unsigned long nr_pages)
 
        /* removal success */
        adjust_managed_page_count(pfn_to_page(start_pfn), -nr_pages);
-       zone->present_pages -= nr_pages;
-
-       pgdat_resize_lock(zone->zone_pgdat, &flags);
-       zone->zone_pgdat->node_present_pages -= nr_pages;
-       pgdat_resize_unlock(zone->zone_pgdat, &flags);
+       adjust_present_page_count(zone, -nr_pages);
 
        init_per_zone_wmark_min();
 
-- 
2.16.3