mm/mm_init.c: remove reset_node_present_pages()

reset_node_present_pages() only get called in hotadd_init_pgdat(), move
the action that clear present pages to free_area_init_core_hotplug(), so
the helper can be removed.

Link: https://lkml.kernel.org/r/20230607025056.1348-1-haifeng.xu@shopee.comSigned-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/memory_hotplug.c

@@ -1156,16 +1156,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 	return ret;
 }
 
-static void reset_node_present_pages(pg_data_t *pgdat)
-{
-	struct zone *z;
-
-	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
-		z->present_pages = 0;
-
-	pgdat->node_present_pages = 0;
-}
-
 /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
 static pg_data_t __ref *hotadd_init_pgdat(int nid)
 {
@@ -1188,14 +1178,6 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid)
 	 */
 	build_all_zonelists(pgdat);
 
-	/*
-	 * When memory is hot-added, all the memory is in offline state. So
-	 * clear all zones' present_pages because they will be updated in
-	 * online_pages() and offline_pages().
-	 * TODO: should be in free_area_init_core_hotplug?
-	 */
-	reset_node_present_pages(pgdat);
-
 	return pgdat;
 }
 

mm/mm_init.c

@@ -1509,6 +1509,8 @@ void __ref free_area_init_core_hotplug(struct pglist_data *pgdat)
 	pgdat->kswapd_order = 0;
 	pgdat->kswapd_highest_zoneidx = 0;
 	pgdat->node_start_pfn = 0;
+	pgdat->node_present_pages = 0;
+
 	for_each_online_cpu(cpu) {
 		struct per_cpu_nodestat *p;
 
@@ -1516,8 +1518,17 @@ void __ref free_area_init_core_hotplug(struct pglist_data *pgdat)
 		memset(p, 0, sizeof(*p));
 	}
 
-	for (z = 0; z < MAX_NR_ZONES; z++)
-		zone_init_internals(&pgdat->node_zones[z], z, nid, 0);
+	/*
+	 * When memory is hot-added, all the memory is in offline state. So
+	 * clear all zones' present_pages and managed_pages because they will
+	 * be updated in online_pages() and offline_pages().
+	 */
+	for (z = 0; z < MAX_NR_ZONES; z++) {
+		struct zone *zone = pgdat->node_zones + z;
+
+		zone->present_pages = 0;
+		zone_init_internals(zone, z, nid, 0);
+	}
 }
 #endif