writeback: make wakeup_dirtytime_writeback() handle multiple bdi_writeback's

wakeup_dirtytime_writeback() currently only starts writeback on the
root wb (bdi_writeback).  For cgroup writeback support, update the
function to check all wbs.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Tejun Heo 2015-05-22 17:13:56 -04:00 committed by Jens Axboe
parent f2b6512160
commit 001fe6f617

View File

@ -1260,9 +1260,12 @@ static void wakeup_dirtytime_writeback(struct work_struct *w)
rcu_read_lock();
list_for_each_entry_rcu(bdi, &bdi_list, bdi_list) {
if (list_empty(&bdi->wb.b_dirty_time))
continue;
wb_wakeup(&bdi->wb);
struct bdi_writeback *wb;
struct wb_iter iter;
bdi_for_each_wb(wb, bdi, &iter, 0)
if (!list_empty(&bdi->wb.b_dirty_time))
wb_wakeup(&bdi->wb);
}
rcu_read_unlock();
schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);