On 6/21/22 01:11, Jan Kara wrote:
> blkcg->ioprio_set field is not really useful except for avoiding
> possibly more expensive checks inside blkcg_ioprio_track(). The check
> for blkcg->prio_policy being equal to POLICY_NO_CHANGE does the same
> service so just remove the ioprio_set field and replace the check.
>
> Signed-off-by: Jan Kara <jack@xxxxxxx>
Looks good to me.
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
> ---
> block/blk-ioprio.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/block/blk-ioprio.c b/block/blk-ioprio.c
> index 79e797f5d194..3f605583598b 100644
> --- a/block/blk-ioprio.c
> +++ b/block/blk-ioprio.c
> @@ -62,7 +62,6 @@ struct ioprio_blkg {
> struct ioprio_blkcg {
> struct blkcg_policy_data cpd;
> enum prio_policy prio_policy;
> - bool prio_set;
> };
>
> static inline struct ioprio_blkg *pd_to_ioprio(struct blkg_policy_data *pd)
> @@ -113,7 +112,6 @@ static ssize_t ioprio_set_prio_policy(struct kernfs_open_file *of, char *buf,
> if (ret < 0)
> return ret;
> blkcg->prio_policy = ret;
> - blkcg->prio_set = true;
> return nbytes;
> }
>
> @@ -193,16 +191,15 @@ static void blkcg_ioprio_track(struct rq_qos *rqos, struct request *rq,
> struct ioprio_blkcg *blkcg = ioprio_blkcg_from_bio(bio);
> u16 prio;
>
> - if (!blkcg->prio_set)
> + if (blkcg->prio_policy == POLICY_NO_CHANGE)
> return;
>
> /*
> * Except for IOPRIO_CLASS_NONE, higher I/O priority numbers
> * correspond to a lower priority. Hence, the max_t() below selects
> * the lower priority of bi_ioprio and the cgroup I/O priority class.
> - * If the cgroup policy has been set to POLICY_NO_CHANGE == 0, the
> - * bio I/O priority is not modified. If the bio I/O priority equals
> - * IOPRIO_CLASS_NONE, the cgroup I/O priority is assigned to the bio.
> + * If the bio I/O priority equals IOPRIO_CLASS_NONE, the cgroup I/O
> + * priority is assigned to the bio.
> */
> prio = max_t(u16, bio->bi_ioprio,
> IOPRIO_PRIO_VALUE(blkcg->prio_policy, 0));
--
Damien Le Moal
Western Digital Research
