On 8/31/25 8:32 PM, Yu Kuai wrote:
> @@ -372,7 +372,10 @@ static inline void blkg_put(struct blkcg_gq *blkg)
> 
>   static inline void blkcg_bio_issue_init(struct bio *bio)
>   {
> -	bio->issue_time_ns = blk_time_get_ns();
> +	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
> +
> +	if (test_bit(QUEUE_FLAG_BIO_ISSUE, &q->queue_flags))
> +		bio->issue_time_ns = blk_time_get_ns();
>   }
> 
>   static inline void blkcg_use_delay(struct blkcg_gq *blkg)
> diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
> index 554b191a6892..c9b3bd12c87c 100644
> --- a/block/blk-iolatency.c
> +++ b/block/blk-iolatency.c
> @@ -767,6 +767,7 @@ static int blk_iolatency_init(struct gendisk *disk)
>   	if (ret)
>   		goto err_qos_del;
> 
> +	blk_queue_flag_set(QUEUE_FLAG_BIO_ISSUE, disk->queue);
>   	timer_setup(&blkiolat->timer, blkiolatency_timer_fn, 0);
>   	INIT_WORK(&blkiolat->enable_work, blkiolatency_enable_work_fn);

Shouldn't QUEUE_FLAG_BIO_ISSUE be cleared when initializing
bio->issue_time_ns is no longer necessary?

Thanks,

Bart.