On 20.10.2016 15:38, zhouxianr...@huawei.com wrote:
> From: z00281421 <z00281...@notesmail.huawei.com>
>
> The bdi flusher should be throttled only depends on
> own bdi and is decoupled with others.
>
> separate PGDAT_WRITEBACK into PGDAT_ANON_WRITEBACK and
> PGDAT_FILE_WRITEBACK avoid scanning anon lru and it is ok
> then throttled on file WRITEBACK.
>
> i think above may be not right.
>
> Signed-off-by: z00281421 <z00281...@notesmail.huawei.com>
> ---
> fs/fs-writeback.c | 8 ++++++--
> include/linux/mmzone.h | 7 +++++--
> mm/vmscan.c | 20 ++++++++++++--------
> 3 files changed, 23 insertions(+), 12 deletions(-)
>
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index 05713a5..ddcc70f 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -1905,10 +1905,13 @@ void wb_workfn(struct work_struct *work)
> {
> struct bdi_writeback *wb = container_of(to_delayed_work(work),
> struct bdi_writeback, dwork);
> + struct backing_dev_info *bdi = container_of(to_delayed_work(work),
> + struct backing_dev_info,
> wb.dwork);
> long pages_written;
>
> set_worker_desc("flush-%s", dev_name(wb->bdi->dev));
> - current->flags |= PF_SWAPWRITE;
> + current->flags |= (PF_SWAPWRITE | PF_LESS_THROTTLE);
> + current->bdi = bdi;
>
> if (likely(!current_is_workqueue_rescuer() ||
> !test_bit(WB_registered, &wb->state))) {
> @@ -1938,7 +1941,8 @@ void wb_workfn(struct work_struct *work)
> else if (wb_has_dirty_io(wb) && dirty_writeback_interval)
> wb_wakeup_delayed(wb);
>
> - current->flags &= ~PF_SWAPWRITE;
> + current->bdi = NULL;
> + current->flags &= ~(PF_SWAPWRITE | PF_LESS_THROTTLE);
> }
>
> /*
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index 7f2ae99..fa602e9 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -528,8 +528,11 @@ enum pgdat_flags {
> * many dirty file pages at the tail
> * of the LRU.
> */
> - PGDAT_WRITEBACK, /* reclaim scanning has recently found
> - * many pages under writeback
> + PGDAT_ANON_WRITEBACK, /* reclaim scanning has recently found
> + * many anonymous pages under writeback
> + */
> + PGDAT_FILE_WRITEBACK, /* reclaim scanning has recently found
> + * many file pages under writeback
> */
> PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */
Nobody seems to be clearing those bits (same was with PGDAT_WRITEBACK) ?
--Mika
