From a78418e6a04c93b9ffd3f0f601c5cb10612acb7f Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 23 Jun 2022 09:48:34 +0200 Subject: [PATCH] block: Always initialize bio IO priority on submit Currently, IO priority set in task's IO context is not reflected in the bio->bi_ioprio for most IO (only io_uring and direct IO set it). This results in odd results where process is submitting some bios with one priority and other bios with a different (unset) priority and due to differing priorities bios cannot be merged. Make sure bio->bi_ioprio is always set on bio submission. Reviewed-by: Damien Le Moal Tested-by: Damien Le Moal Signed-off-by: Jan Kara Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20220623074840.5960-9-jack@suse.cz Signed-off-by: Jens Axboe --- block/blk-mq.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index c0ec1938feee..92aae03103b7 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2782,6 +2782,9 @@ static inline struct request *blk_mq_get_cached_request(struct request_queue *q, static void bio_set_ioprio(struct bio *bio) { + /* Nobody set ioprio so far? Initialize it based on task's nice value */ + if (IOPRIO_PRIO_CLASS(bio->bi_ioprio) == IOPRIO_CLASS_NONE) + bio->bi_ioprio = get_current_ioprio(); blkcg_set_ioprio(bio); }