From: Jens Axboe <axboe@fb.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>, Matias Bj??rling <m@bjorling.me>,
<linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] null_blk: Register as a LightNVM device
Date: Thu, 12 Nov 2015 09:00:20 -0700 [thread overview]
Message-ID: <5644B794.6070509@fb.com> (raw)
In-Reply-To: <20151112155831.GA9562@infradead.org>
On 11/12/2015 08:58 AM, Christoph Hellwig wrote:
> On Thu, Nov 12, 2015 at 08:54:48AM -0700, Jens Axboe wrote:
>>> 300 lines of boilerplate for just setting up a few request_queues seem
>>> wrong, can you show the actual patch you measured?
>>
>> I just took it from Matias' last posting:
>>
>> http://marc.info/?l=linux-kernel&m=144605858228534&w=2
>
> Well, that one has all these crazy completion methods which
> are of no use for a blk-mq driver, so it should really be
> compared without those.
So we can cut it down a bit, it's still going to be the same boilerplate
code that null_blk has, even with just mq completions. If it ended up
rewriting null_blk to be something else entirely or full of ifdef
sprinkles, I'd agree. But for adding a hundred lines of code to be able
to test lightnvm perf, I think it's a no-brainer to just add it to
null_blk and not have a separate module.
--
Jens Axboe
next prev parent reply other threads:[~2015-11-12 16:00 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-11 10:06 [PATCH] null_blk: Register as a LightNVM device Matias Bjørling
2015-11-11 21:27 ` Jens Axboe
2015-11-11 22:11 ` Jens Axboe
2015-11-12 11:30 ` Matias Bjørling
2015-11-12 8:53 ` Christoph Hellwig
2015-11-12 15:49 ` Jens Axboe
2015-11-12 15:52 ` Christoph Hellwig
2015-11-12 15:54 ` Jens Axboe
2015-11-12 15:58 ` Christoph Hellwig
2015-11-12 16:00 ` Jens Axboe [this message]
2015-11-12 18:29 ` Matias Bjørling
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5644B794.6070509@fb.com \
--to=axboe@fb.com \
--cc=axboe@kernel.dk \
--cc=hch@infradead.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=m@bjorling.me \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.