Subject: Re: [PATCH 5/7] blk-mq-sched: add framework for MQ capable IO
 schedulers
To: Omar Sandoval <osandov@osandov.com>
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From: Jens Axboe <axboe@fb.com>
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Date: Thu, 15 Dec 2016 14:44:17 -0700
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On 12/15/2016 12:29 PM, Omar Sandoval wrote:
> Hey, Jens, a couple of minor nits below.
> 
> One bigger note: adding the blk_mq_sched_*() helpers and keeping the
> blk_mq_*() helpers that they replaced seems risky. For example,
> blk_mq_free_request() is superseded by blk_mq_sched_put_request(), but
> we kept blk_mq_free_request(). There are definitely some codepaths that
> are still using blk_mq_free_request() that are now wrong
> (__nvme_submit_user_cmd() is the most obvious one I saw).
> 
> Can we get rid of the old, non-sched functions? Or maybe even make old
> interface do the sched stuff instead of adding blk_mq_sched_*()?

I fixed this up. blk_mq_free_request() is now what we still use as an
exported interface, and that just calls blk_mq_sched_put_request().  The
old (__)blk_mq_free_request() are now (__)blk_mq_finish_request() and
internal only.

-- 
Jens Axboe