[PATCH v4 26/36] mm: Avoid splitting large pages

Matthew Wilcox
2020-05-15T13:40:11Z

If the filesystem supports large pages, then do not split them before
removing them from the page cache; remove them as a unit.
---
mm/vmscan.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index b06868fc4926..51e6c135575d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1271,9 +1271,10 @@ static unsigned long shrink_page_list(struct list_head *page_list,
/* Adding to swap updated mapping */
mapping = page_mapping(page);
}
- } else if (unlikely(PageTransHuge(page))) {
+ } else if (PageTransHuge(page)) {
/* Split file THP */
- if (split_huge_page_to_list(page, page_list))
+ if (!mapping_large_pages(mapping) &&
+ split_huge_page_to_list(page, page_list))
goto keep_locked;
}

--
2.26.2