diff mbox series

[4/6] khugepaged: Drain LRU add pagevec after swapin

Message ID 20200413100447.20073-5-kirill.shutemov@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series thp/khugepaged improvements and CoW semantics | expand

Commit Message

kirill.shutemov@linux.intel.com April 13, 2020, 10:04 a.m. UTC
__collapse_huge_page_isolate() may fail due to extra pin in the LRU add
pagevec. It's pretty common for swapin case: we swap in pages just to
fail due to the extra pin.

Drain LRU add pagevec on successful swapin.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
 mm/khugepaged.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index ee66c140c2d6..e3e41c2768d8 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -934,6 +934,11 @@  static bool __collapse_huge_page_swapin(struct mm_struct *mm,
 	}
 	vmf.pte--;
 	pte_unmap(vmf.pte);
+
+	/* Drain LRU add pagevec to remove extra pin on the swapped in pages */
+	if (swapped_in)
+		lru_add_drain();
+
 	trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, 1);
 	return true;
 }