diff mbox series

[06/12] mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios

Message ID 20220116121822.1727633-7-willy@infradead.org (mailing list archive)
State New
Headers show
Series Enabling large folios for 5.17 | expand

Commit Message

Matthew Wilcox Jan. 16, 2022, 12:18 p.m. UTC 
A large folio 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 45665874082d..3181bf2f8a37 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1754,7 +1754,8 @@  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);