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Subject: Re: [PATCH 05/12] blk-mq: Introduce blk_mq_quiesce_queue()
To: Hannes Reinecke <hare@suse.de>, Jens Axboe <axboe@fb.com>
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From: Bart Van Assche <bart.vanassche@sandisk.com>
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Date: Thu, 27 Oct 2016 08:56:50 -0700
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On 10/26/2016 10:52 PM, Hannes Reinecke wrote:
> Hmm. Can't say I like having to have two RCU structure for the same
> purpose, but I guess that can't be helped.

Hello Hannes,

There are two RCU structures because of BLK_MQ_F_BLOCKING. Today only 
the nbd driver sets that flag. If the nbd driver would be modified such 
that it doesn't set that flag then the BLK_MQ_F_BLOCKING flag and also 
queue_rq_srcu could be eliminated from the blk-mq core.

Bart.