[PATCH v8 3/8] mm,memory_hotplug: Factor out adjusting present pages into adjust_present_page_count()

From: Oscar Salvador
Date: Fri Apr 16 2021 - 06:22:10 EST


From: David Hildenbrand <david@xxxxxxxxxx>

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 <david@xxxxxxxxxx>
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
Reviewed-by: Oscar Salvador <osalvador@xxxxxxx>
---
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