[PATCH 13/14] blk-mq: add tagset quiesce interface

[Chaitanya Kulkarni]

On 11/1/22 08:00, Christoph Hellwig wrote:
> From: Chao Leng <lengchao at huawei.com>
> 
> Drivers that have shared tagsets may need to quiesce potentially a lot
> of request queues that all share a single tagset (e.g. nvme). Add an
> interface to quiesce all the queues on a given tagset. This interface is
> useful because it can speedup the quiesce by doing it in parallel.
> 
> Because some queues should not need to be quiesced (e.g. the nvme
> connect_q) when quiescing the tagset, introduce a
> QUEUE_FLAG_SKIP_TAGSET_QUIESCE flag to allow this new interface to
> ski quiescing a particular queue.
> 
> Signed-off-by: Chao Leng <lengchao at huawei.com>
> [hch: simplify for the per-tag_set srcu_struct]
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> Reviewed-by: Keith Busch <kbusch at kernel.org>
> Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
> Reviewed-by: Ming Lei <ming.lei at redhat.com>
> Reviewed-by: Chao Leng <lengchao at huawei.com>
> Reviewed-by: Hannes Reinecke <hare at suse.de>
> ---
>

Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>

-ck