mm/vmscan: reclaim only affects managed_zones

As mentioned in commit 6aa303de ("mm, vmscan: only allocate and
reclaim from zones with pages managed by the buddy allocator") , reclaim
only affects managed_zones.

Let's adjust the code and comment accordingly.

Link: https://lkml.kernel.org/r/20220327024101.10378-1-richard.weiyang@gmail.comSigned-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmscan.c

@@ -1031,7 +1031,7 @@ static bool skip_throttle_noprogress(pg_data_t *pgdat)
 	for (i = 0; i < MAX_NR_ZONES; i++) {
 		struct zone *zone = pgdat->node_zones + i;
 
-		if (!populated_zone(zone))
+		if (!managed_zone(zone))
 			continue;
 
 		reclaimable += zone_reclaimable_pages(zone);
@@ -3912,7 +3912,7 @@ static bool pgdat_balanced(pg_data_t *pgdat, int order, int highest_zoneidx)
 	}
 
 	/*
-	 * If a node has no populated zone within highest_zoneidx, it does not
+	 * If a node has no managed zone within highest_zoneidx, it does not
 	 * need balancing by definition. This can happen if a zone-restricted
 	 * allocation tries to wake a remote kswapd.
 	 */