Re: [PATCH v6 2/8] blk-mq-sched: unify elevators checking for async requests

[Hannes Reinecke]

On 11/21/25 06:28, Yu Kuai wrote:
> bfq and mq-deadline consider sync writes as async requests and only
> reserve tags for sync reads by async_depth, however, kyber doesn't
> consider sync writes as async requests for now.
>
> Consider the case there are lots of dirty pages, and user use fsync to
> flush dirty pages. In this case sched_tags can be exhausted by sync writes
> and sync reads can stuck waiting for tag. Hence let kyber follow what
> mq-deadline and bfq did, and unify async requests checking for all
> elevators.
>
> Signed-off-by: Yu Kuai <yukuai@xxxxxxxxx>
> Reviewed-by: Nilay Shroff <nilay@xxxxxxxxxxxxx>
> ---
>   block/bfq-iosched.c   | 2 +-
>   block/blk-mq-sched.h  | 5 +++++
>   block/kyber-iosched.c | 2 +-
>   block/mq-deadline.c   | 2 +-
>   4 files changed, 8 insertions(+), 3 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
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