Re: [PATCH 2/7] fs: kill 'nr_pages' argument from wakeup_flusher_threads()

From: Jan Kara
Date: Fri Sep 22 2017 - 09:12:42 EST


On Wed 20-09-17 09:32:57, Jens Axboe wrote:
> Everybody is passing in 0 now, let's get rid of the argument.
>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>

Looks good. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza


> ---
> fs/buffer.c | 2 +-
> fs/fs-writeback.c | 9 ++++-----
> fs/sync.c | 2 +-
> include/linux/writeback.h | 2 +-
> mm/vmscan.c | 2 +-
> 5 files changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index 9471a445e370..cf71926797d3 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -260,7 +260,7 @@ static void free_more_memory(void)
> struct zoneref *z;
> int nid;
>
> - wakeup_flusher_threads(0, WB_REASON_FREE_MORE_MEM);
> + wakeup_flusher_threads(WB_REASON_FREE_MORE_MEM);
> yield();
>
> for_each_online_node(nid) {
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index 245c430a2e41..bb6148dc6d24 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -1947,12 +1947,12 @@ void wb_workfn(struct work_struct *work)
> }
>
> /*
> - * Start writeback of `nr_pages' pages. If `nr_pages' is zero, write back
> - * the whole world.
> + * Wakeup the flusher threads to start writeback of all currently dirty pages
> */
> -void wakeup_flusher_threads(long nr_pages, enum wb_reason reason)
> +void wakeup_flusher_threads(enum wb_reason reason)
> {
> struct backing_dev_info *bdi;
> + long nr_pages;
>
> /*
> * If we are expecting writeback progress we must submit plugged IO.
> @@ -1960,8 +1960,7 @@ void wakeup_flusher_threads(long nr_pages, enum wb_reason reason)
> if (blk_needs_flush_plug(current))
> blk_schedule_flush_plug(current);
>
> - if (!nr_pages)
> - nr_pages = get_nr_dirty_pages();
> + nr_pages = get_nr_dirty_pages();
>
> rcu_read_lock();
> list_for_each_entry_rcu(bdi, &bdi_list, bdi_list) {
> diff --git a/fs/sync.c b/fs/sync.c
> index a576aa2e6b09..09f96a18dd93 100644
> --- a/fs/sync.c
> +++ b/fs/sync.c
> @@ -108,7 +108,7 @@ SYSCALL_DEFINE0(sync)
> {
> int nowait = 0, wait = 1;
>
> - wakeup_flusher_threads(0, WB_REASON_SYNC);
> + wakeup_flusher_threads(WB_REASON_SYNC);
> iterate_supers(sync_inodes_one_sb, NULL);
> iterate_supers(sync_fs_one_sb, &nowait);
> iterate_supers(sync_fs_one_sb, &wait);
> diff --git a/include/linux/writeback.h b/include/linux/writeback.h
> index d5815794416c..1f9c6db5e29a 100644
> --- a/include/linux/writeback.h
> +++ b/include/linux/writeback.h
> @@ -189,7 +189,7 @@ bool try_to_writeback_inodes_sb(struct super_block *, enum wb_reason reason);
> bool try_to_writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
> enum wb_reason reason);
> void sync_inodes_sb(struct super_block *);
> -void wakeup_flusher_threads(long nr_pages, enum wb_reason reason);
> +void wakeup_flusher_threads(enum wb_reason reason);
> void inode_wait_for_writeback(struct inode *inode);
>
> /* writeback.h requires fs.h; it, too, is not included from here. */
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 13d711dd8776..42a7fdd52d87 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -1867,7 +1867,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
> * also allow kswapd to start writing pages during reclaim.
> */
> if (stat.nr_unqueued_dirty == nr_taken) {
> - wakeup_flusher_threads(0, WB_REASON_VMSCAN);
> + wakeup_flusher_threads(WB_REASON_VMSCAN);
> set_bit(PGDAT_DIRTY, &pgdat->flags);
> }
>
> --
> 2.7.4
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR