[11/14] mm: use SWP_SYNCHRONOUS_IO more intelligently
diff mbox series

Message ID 20200722062552.212200-12-hch@lst.de
State New
Headers show
Series
  • [01/14] fs: remove the unused SB_I_MULTIROOT flag
Related show

Commit Message

Christoph Hellwig July 22, 2020, 6:25 a.m. UTC
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(-)

Comments

Shakeel Butt July 22, 2020, 4:26 p.m. UTC | #1
On Tue, Jul 21, 2020 at 11:27 PM Christoph Hellwig <hch@lst.de> wrote:
>
> 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..442061348dfb26 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) {

!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
>

Patch
diff mbox series

diff --git a/mm/page_io.c b/mm/page_io.c
index ccda7679008851..442061348dfb26 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;