[PATCH] mm: remove lru_add_drain_all in alloc_contig_range

[Minchan Kim]

__alloc_contig_migrate_range already has lru_add_drain_all call
via migrate_prep. It's necessary to move LRU taget pages into
LRU list to be able to isolated. However, lru_add_drain_all call
after __alloc_contig_migrate_range is called is pointless.

This patch removes it.

Signed-off-by: Minchan Kim <minc...@kernel.org>
---
 mm/page_alloc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6446778cbc6b..f8fbee73dd6d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8603,8 +8603,6 @@ int alloc_contig_range(unsigned long start, unsigned long 
end,
         * isolated thus they won't get removed from buddy.
         */
 
-       lru_add_drain_all();
-
        order = 0;
        outer_start = start;
        while (!PageBuddy(pfn_to_page(outer_start))) {
-- 
2.30.0.478.g8a0d178c01-goog