[PATCH] mm: Fix buddy list helpers

From: Dan Williams
Date: Sat Feb 16 2019 - 12:22:08 EST


Tetsuo reports that free page statistics are not reporting correctly,
and Vlastimil noticed that "mm: Move buddy list manipulations into
helpers" botched one of its conversions of add_to_free_area(). Fix the
double-increment of ->nr_free.

Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Reported-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Tested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
Hi Andrew,

Please fold this into
mm-move-buddy-list-manipulations-into-helpers.patch.

mm/page_alloc.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2a0969e3b0eb..da537fc39c54 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1851,7 +1851,6 @@ static inline void expand(struct zone *zone, struct page *page,
continue;

add_to_free_area(&page[size], area, migratetype);
- area->nr_free++;
set_page_order(&page[size], high);
}
}