Date: Fri, 22 Apr 2005 13:37:50 +0200
From: Jens Axboe <axboe@suse.de>
To: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Tejun Heo <htejun@gmail.com>, Christoph Hellwig <hch@infradead.org>,
       SCSI Mailing List <linux-scsi@vger.kernel.org>,
       Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH scsi-misc-2.6 03/05] scsi: make scsi_queue_insert() use blk_requeue_request()
Message-ID: <20050422113749.GZ9371@suse.de>
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On Thu, Apr 21 2005, James Bottomley wrote:
> On Thu, 2005-04-21 at 08:10 +0200, Jens Axboe wrote:
> > I wondered about this action recently myself. What is the point in
> > requeueing this request, only to call scsi_run_queue() ->
> > blk_run_queue() -> issue same request. If the point really is to reissue
> > the request immediately, I can think of many ways more efficient than
> > this :-)
> 
> Well ... that's because the logic that decides whether to plug the queue
> or simply exit is in the scsi_request_fn().  That's what the comment is
> about.  We could abstract the check into a function, but (unless you
> have any suggestions on rewording it) I thought the comment made what
> was going on reasonably clear.
> 

Looks fine, I just missed enough code context in the patch to see this.
Since requeuing probably isn't all that uncommon, it may make sense to
optimize this a little though.

-- 
Jens Axboe

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