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Date: Fri, 24 Mar 2017 11:03:31 -0700
From: Omar Sandoval <osandov@osandov.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>
Subject: Re: [PATCH] blk-mq: include errors in did_work calculation
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On Fri, Mar 24, 2017 at 11:39:10AM -0600, Jens Axboe wrote:
> Currently we return true in blk_mq_dispatch_rq_list() if we queued IO
> successfully, but we really want to return whether or not the we made
> progress. Progress includes if we got an error return.  If we don't,
> this can lead to a hang in blk_mq_sched_dispatch_requests() when a
> driver is draining IO by returning BLK_MQ_QUEUE_ERROR instead of
> manually ending the IO in error and return BLK_MQ_QUEUE_OK.
> 
> Signed-off-by: Jens Axboe <axboe@fb.com>

Reviewed-by: Omar Sandoval <osandov@fb.com>