nr_none is always 0 for non-shmem case because the page can be read from
the backend store. So when nr_none ! = 0, it must be in is_shmem case.
Also only adjust the nrpages and uncharge shmem when nr_none != 0 to save
cpu cycles.
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Zach O'Keefe <zokeefe@xxxxxxxxxx>
---
mm/khugepaged.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index a36d9746c321..47514f2fabb9 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1852,8 +1852,8 @@ static void collapse_file(struct mm_struct *mm,
if (nr_none) {
__mod_lruvec_page_state(new_page, NR_FILE_PAGES, nr_none);
- if (is_shmem)
- __mod_lruvec_page_state(new_page, NR_SHMEM, nr_none);
+ /* nr_none is always 0 for non-shmem. */
+ __mod_lruvec_page_state(new_page, NR_SHMEM, nr_none);
}
/* Join all the small entries into a single multi-index entry */
@@ -1917,10 +1917,10 @@ static void collapse_file(struct mm_struct *mm,
/* Something went wrong: roll back page cache changes */
xas_lock_irq(&xas);
- mapping->nrpages -= nr_none;
-
- if (is_shmem)
+ if (nr_none) {
+ mapping->nrpages -= nr_none;
shmem_uncharge(mapping->host, nr_none);
+ }
xas_set(&xas, start);
xas_for_each(&xas, page, end - 1) {
--
2.23.0
