2024-02-28 01:25:23

by Kemeng Shi

Subject: [PATCH v2 4/6] fs/writeback: only calculate dirtied_before when b_io is empty

The dirtied_before is only used when b_io is not empty, so only calculate
when b_io is not empty.

Signed-off-by: Kemeng Shi <[email protected]>
---
fs/fs-writeback.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 1c3134817865..c98684e9e6ba 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2105,20 +2105,21 @@ static long wb_writeback(struct bdi_writeback *wb,

spin_lock(&wb->list_lock);

- /*
- * Kupdate and background works are special and we want to
- * include all inodes that need writing. Livelock avoidance is
- * handled by these works yielding to any other work so we are
- * safe.
- */
- if (work->for_kupdate) {
- dirtied_before = jiffies -
- msecs_to_jiffies(dirty_expire_interval * 10);
- } else if (work->for_background)
- dirtied_before = jiffies;
-
trace_writeback_start(wb, work);
if (list_empty(&wb->b_io)) {
+ /*
+ * Kupdate and background works are special and we want
+ * to include all inodes that need writing. Livelock
+ * avoidance is handled by these works yielding to any
+ * other work so we are safe.
+ */
+ if (work->for_kupdate) {
+ dirtied_before = jiffies -
+ msecs_to_jiffies(dirty_expire_interval *
+ 10);
+ } else if (work->for_background)
+ dirtied_before = jiffies;
+
queue_io(wb, work, dirtied_before);
queued = true;
}
--
2.30.0

2024-03-18 17:23:00

by Jan Kara

Subject: Re: [PATCH v2 4/6] fs/writeback: only calculate dirtied_before when b_io is empty

On Wed 28-02-24 17:19:56, Kemeng Shi wrote:
> The dirtied_before is only used when b_io is not empty, so only calculate
> when b_io is not empty.
>
> Signed-off-by: Kemeng Shi <[email protected]>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -2105,20 +2105,21 @@ static long wb_writeback(struct bdi_writeback *wb,
>
> spin_lock(&wb->list_lock);
>
> - /*
> - * Kupdate and background works are special and we want to
> - * include all inodes that need writing. Livelock avoidance is
> - * handled by these works yielding to any other work so we are
> - * safe.
> - */
> - if (work->for_kupdate) {
> - dirtied_before = jiffies -
> - msecs_to_jiffies(dirty_expire_interval * 10);
> - } else if (work->for_background)
> - dirtied_before = jiffies;
> -
> trace_writeback_start(wb, work);
> if (list_empty(&wb->b_io)) {
> + /*
> + * Kupdate and background works are special and we want
> + * to include all inodes that need writing. Livelock
> + * avoidance is handled by these works yielding to any
> + * other work so we are safe.
> + */
> + if (work->for_kupdate) {
> + dirtied_before = jiffies -
> + msecs_to_jiffies(dirty_expire_interval *
> + 10);
> + } else if (work->for_background)
> + dirtied_before = jiffies;
> +
> queue_io(wb, work, dirtied_before);
> queued = true;
> }
> --
> 2.30.0
>
--
Jan Kara <[email protected]>
SUSE Labs, CR