On Nov 02, 2021 / 23:36, Ming Lei wrote:
> In case of shared tags and none io sched, batched completion still may
> be run into, and hctx->nr_active is accounted when getting driver tag,
> so it has to be updated in blk_mq_end_request_batch().
>
> Otherwise, hctx->nr_active may become same with queue depth, then
> hctx_may_queue() always return false, then io hang is caused.
>
> Fixes the issue by updating the counter in batched way.
>
> Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
> Fixes: f794f3351f26 ("block: add support for blk_mq_end_request_batch()")
> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Ming, thank you very much. I have confirmed that the blktests block/005 hang
disappears using NVMe devices with two namespaces.
Though this patch is already queued up to for-5.16/block, in case it is still
meaningful:
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
--
Best Regards,
Shin'ichiro Kawasaki
