RE: [RFC PATCH 1/4] scsi: Allow drivers to set BLK_MQ_F_BLOCKING

[Daejun Park <daejun7.park@xxxxxxxxxxx>]

Hi Mike, 

>@@ -2952,8 +2954,8 @@ scsi_host_block(struct Scsi_Host *shost)
>         }
> 
>         /*
>-         * SCSI never enables blk-mq's BLK_MQ_F_BLOCKING flag so
>-         * calling synchronize_rcu() once is enough.
>+         * Drivers that use this helper enable blk-mq's BLK_MQ_F_BLOCKING flag
>+         * so calling synchronize_rcu() once is enough.
>          */
>         WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING);
Should we keep this line?

And I think scsi_host_block() should call synchronize_srcu() rather than
synchronize_rcu(), if the BLK_MQ_F_BLOCKING flag is used.

Thanks,
Daejun