| From 5de0073fcd50cc1f150895a7bb04d3cf8067b1d7 Mon Sep 17 00:00:00 2001 |
| From: Tejun Heo <tj@kernel.org> |
| Date: Thu, 13 Jun 2019 15:30:37 -0700 |
| Subject: blk-iolatency: clear use_delay when io.latency is set to zero |
| |
| From: Tejun Heo <tj@kernel.org> |
| |
| commit 5de0073fcd50cc1f150895a7bb04d3cf8067b1d7 upstream. |
| |
| If use_delay was non-zero when the latency target of a cgroup was set |
| to zero, it will stay stuck until io.latency is enabled on the cgroup |
| again. This keeps readahead disabled for the cgroup impacting |
| performance negatively. |
| |
| Signed-off-by: Tejun Heo <tj@kernel.org> |
| Cc: Josef Bacik <jbacik@fb.com> |
| Fixes: d70675121546 ("block: introduce blk-iolatency io controller") |
| Cc: stable@vger.kernel.org # v4.19+ |
| Signed-off-by: Jens Axboe <axboe@kernel.dk> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| block/blk-iolatency.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| --- a/block/blk-iolatency.c |
| +++ b/block/blk-iolatency.c |
| @@ -746,8 +746,10 @@ static int iolatency_set_min_lat_nsec(st |
| |
| if (!oldval && val) |
| return 1; |
| - if (oldval && !val) |
| + if (oldval && !val) { |
| + blkcg_clear_delay(blkg); |
| return -1; |
| + } |
| return 0; |
| } |
| |
