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Date: Tue, 27 May 2014 12:38:15 -0600
From: Jens Axboe <axboe@kernel.dk>
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To: Christoph Hellwig <hch@lst.de>, Ming Lei <tom.leiming@gmail.com>
CC: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH] block: mq flush: fix race between IPI handler and mq
 flush worker
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On 2014-05-27 12:13, Christoph Hellwig wrote:
> Here is my counter proposal that requeues via two lists and a work struct
> in the request_queue.  I've also tested it with scsi-mq.
>

I like this, moves the state out of the request. But how about we 
consolidate the two requeue requests lists, and just mark the request as 
needing head insertion instead? Just add a cmd_flags flag, 
REQ_REQUEUE_HEAD or something.

-- 
Jens Axboe