[PATCH 11/14] mm: use SWP_SYNCHRONOUS_IO more intelligently
From: Christoph Hellwig <hch@lst.de>
Date: 2020-07-26 15:04:31
Also in:
dm-devel, linux-block, linux-fsdevel, linux-mm, linux-raid, lkml
Subsystem:
memory management, memory management - swap, the rest · Maintainers:
Andrew Morton, Chris Li, Kairui Song, Linus Torvalds
There is no point in trying to call bdev_read_page if SWP_SYNCHRONOUS_IO is not set, as the device won't support it. Signed-off-by: Christoph Hellwig <hch@lst.de> --- mm/page_io.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/mm/page_io.c b/mm/page_io.c
index ccda7679008851..7eef3c84766abc 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c@@ -403,15 +403,17 @@ int swap_readpage(struct page *page, bool synchronous) goto out; } - ret = bdev_read_page(sis->bdev, swap_page_sector(page), page); - if (!ret) { - if (trylock_page(page)) { - swap_slot_free_notify(page); - unlock_page(page); - } + if (sis->flags & SWP_SYNCHRONOUS_IO) { + ret = bdev_read_page(sis->bdev, swap_page_sector(page), page); + if (!ret) { + if (trylock_page(page)) { + swap_slot_free_notify(page); + unlock_page(page); + } - count_vm_event(PSWPIN); - goto out; + count_vm_event(PSWPIN); + goto out; + } } ret = 0;
--
2.27.0