+ mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: mm,memory_hotplug: factor out adjusting present pages into adjust_present_page_count()
has been added to the -mm tree.  Its filename is
     mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count.patch

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------------------------------------------------------
From: David Hildenbrand <david@redhat.com>
Subject: mm,memory_hotplug: factor out adjusting present pages into adjust_present_page_count()

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.

Link: https://lkml.kernel.org/r/20210416112411.9826-4-osalvador@suse.de
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory_hotplug.c |   22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

--- a/mm/memory_hotplug.c~mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count
+++ a/mm/memory_hotplug.c
@@ -829,6 +829,16 @@ struct zone * zone_for_pfn_range(int onl
 	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
 	}
 
 	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)
@@ -1702,11 +1708,7 @@ int __ref offline_pages(unsigned long st
 
 	/* 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();
 
_

Patches currently in -mm which might be from david@redhat.com are

mm-page_alloc-drop-pr_info_ratelimited-in-alloc_contig_range.patch
mmmemory_hotplug-factor-out-adjusting-present-pages-into-adjust_present_page_count.patch
kernel-resource-make-walk_system_ram_res-find-all-busy-ioresource_system_ram-resources.patch
kernel-resource-make-walk_mem_res-find-all-busy-ioresource_mem-resources.patch
kernel-resource-remove-first_lvl-siblings_only-logic.patch
drivers-char-remove-dev-kmem-for-good.patch
mm-remove-xlate_dev_kmem_ptr.patch
mm-vmalloc-remove-vwrite.patch