diff mbox series

[v14,136/138] mm/vmscan: Optimise shrink_page_list for smaller THPs

Message ID 20210715033704.692967-137-willy@infradead.org (mailing list archive)
State New
Headers show
Series Memory folios | expand

Commit Message

Matthew Wilcox July 15, 2021, 3:37 a.m. UTC 
A THP which is smaller than a PMD does not need to do the extra work
in try_to_unmap() of trying to split a PMD entry.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 mm/vmscan.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 8b17e46dbf32..433956675107 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1496,7 +1496,8 @@  static unsigned int shrink_page_list(struct list_head *page_list,
 			enum ttu_flags flags = TTU_BATCH_FLUSH;
 			bool was_swapbacked = PageSwapBacked(page);
 
-			if (unlikely(PageTransHuge(page)))
+			if (PageTransHuge(page) &&
+					thp_order(page) >= HPAGE_PMD_ORDER)
 				flags |= TTU_SPLIT_HUGE_PMD;
 
 			try_to_unmap(page, flags);