[PATCH V4 5/6] mm: enable MADV_FREE for swapless system
From: Shaohua Li
Date: Wed Feb 22 2017 - 13:52:40 EST
Now MADV_FREE pages can be easily reclaimed even for swapless system. We
can safely enable MADV_FREE for all systems.
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
---
mm/madvise.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/mm/madvise.c b/mm/madvise.c
index 225af7d..5ab4b7b 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -612,13 +612,7 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
case MADV_WILLNEED:
return madvise_willneed(vma, prev, start, end);
case MADV_FREE:
- /*
- * XXX: In this implementation, MADV_FREE works like
- * MADV_DONTNEED on swapless system or full swap.
- */
- if (get_nr_swap_pages() > 0)
- return madvise_free(vma, prev, start, end);
- /* passthrough */
+ return madvise_free(vma, prev, start, end);
case MADV_DONTNEED:
return madvise_dontneed(vma, prev, start, end);
default:
--
2.9.3