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Date: Wed, 13 Apr 2016 15:54:22 -0400
From: Tejun Heo <tj@kernel.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: Linus Walleij <linus.walleij@linaro.org>,
        Paolo Valente <paolo.valente@linaro.org>, Jens Axboe <axboe@kernel.dk>,
        Fabio Checconi <fchecconi@gmail.com>,
        Arianna Avanzini <avanzini.arianna@gmail.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>, Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH RFC 09/22] block, cfq: replace CFQ with the BFQ-v0 I/O
 scheduler
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Hello, Christoph.

On Fri, Mar 04, 2016 at 09:39:47AM -0800, Christoph Hellwig wrote:
> On Sat, Mar 05, 2016 at 12:29:39AM +0700, Linus Walleij wrote:
> > I'm doing a summary of this discussion as a part of presenting
> > Linaro's involvement in Paolo's work. So I try to understand things.
> 
> Btw, can someone explain why you guys waste so much time hacking and
> arguing about a legacy codebase (old request code and I/O schedulers)
> that everyone would really like to see disappear.  Why don't you
> spend your time on blk-mq where you have an entirely clean slate
> for scheduling?

idk, are we gonna duplicate a full disk scheduler on blk-mq path?  I
think it'd be more sensible to make blk-mq call into the old elevator
path for scheduling IOs on rotating rusts.

Thanks.

-- 
tejun