mm: reduce the amount of work done when updating min_free_kbytes

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 516ab623d773c3dbd99f782d62cf62dc16f8ef24..671e6c94fed77f9fef7b6d56663b8d31c64a8847 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3388,25 +3388,33 @@ static void setup_zone_migrate_reserve(struct zone *zone)
                if (page_to_nid(page) != zone_to_nid(zone))
                        continue;
 
-               /* Blocks with reserved pages will never free, skip them. */
-               block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn);
-               if (pageblock_is_reserved(pfn, block_end_pfn))
-                       continue;
-
                block_migratetype = get_pageblock_migratetype(page);
 
-               /* If this block is reserved, account for it */
-               if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) {
-                       reserve--;
-                       continue;
-               }
+               /* Only test what is necessary when the reserves are not met */
+               if (reserve > 0) {
+                       /*
+                        * Blocks with reserved pages will never free, skip
+                        * them.
+                        */
+                       block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn);
+                       if (pageblock_is_reserved(pfn, block_end_pfn))
+                               continue;
 
-               /* Suitable for reserving if this block is movable */
-               if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) {
-                       set_pageblock_migratetype(page, MIGRATE_RESERVE);
-                       move_freepages_block(zone, page, MIGRATE_RESERVE);
-                       reserve--;
-                       continue;
+                       /* If this block is reserved, account for it */
+                       if (block_migratetype == MIGRATE_RESERVE) {
+                               reserve--;
+                               continue;
+                       }
+
+                       /* Suitable for reserving if this block is movable */
+                       if (block_migratetype == MIGRATE_MOVABLE) {
+                               set_pageblock_migratetype(page,
+                                                       MIGRATE_RESERVE);
+                               move_freepages_block(zone, page,
+                                                       MIGRATE_RESERVE);
+                               reserve--;
+                               continue;
+                       }
                }
 
                /*