We need to use count_swpout_vm_event() for sio_write_complete() to get correct counting. Note that THP swap in (if it ever happens) is current accounted 1 for each page, whether HUGE or normal. This is different from swap-out accounting. This patch should be squashed into MM: handle THP in swap_*page_fs() Reported-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Signed-off-by: NeilBrown <neilb@xxxxxxx> --- mm/page_io.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/page_io.c b/mm/page_io.c index d636a3531cad..1b8075ef3418 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -280,8 +280,10 @@ static void sio_write_complete(struct kiocb *iocb, long ret) set_page_dirty(page); ClearPageReclaim(page); } - } else - count_vm_events(PSWPOUT, sio->pages); + } else { + for (p = 0; p < sio->pages; p++) + count_swpout_vm_event(sio->bvec[p].bv_page); + } for (p = 0; p < sio->pages; p++) end_page_writeback(sio->bvec[p].bv_page); -- 2.36.0