[PATCH V5 0/4] blk-mq: implement queue quiesce via percpu_ref for BLK_MQ_F_BLOCKING

[Sagi Grimberg]

> Hi Jens,
> 
> The 1st patch add .mq_quiesce_mutex for serializing quiesce/unquiesce,
> and prepares for replacing srcu with percpu_ref.
> 
> The 2nd patch replaces srcu with percpu_ref.
> 
> The 3rd patch adds tagset quiesce interface.
> 
> The 4th patch applies tagset quiesce interface for NVMe subsystem.

Tested some reset storms and target restarts during traffic with
nvme-tcp.

Seems that no apparent breakage.

So:

Tested-by: Sagi Grimberg <sagi at grimberg.me>