From: Tejun Heo <tj@kernel.org>
To: Wang Jianchao <jianchao.wan9@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>, Josef Bacik <jbacik@fb.com>,
Bart Van Assche <bvanassche@acm.org>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC V4 1/6] blk: prepare to make blk-rq-qos pluggable and modular
Date: Wed, 23 Feb 2022 16:07:51 -1000 [thread overview]
Message-ID: <Yhbod7pJ1X4CGhEZ@slm.duckdns.org> (raw)
In-Reply-To: <efd94670-9d6d-5651-358c-2f88646298cd@gmail.com>
Hello,
On Thu, Feb 24, 2022 at 09:51:04AM +0800, Wang Jianchao wrote:
> The initial version of this patchset has two targets:
> (1) Add a sysfs interface to open/close the policy per device. Then we needn't
> waste cpu cycles and memory if the device doesn't need the policy.
> (2) Make the policies modular, then it easy to maintain the code of policy in
> production environment as we only need to close the policy and replace the
> .ko file.
>
> The loading module when open policy in sysfs interface is just to avoid modprobe
> manually. There is similar operation when switch io scheduler.
Each rq-qos mechanism already needs and has a way to turn off itself.
There's no reason to add another layer on top. If the current way of
disabling isn't efficient, we should improve that instead of adding a new
layer of interface on top.
And please don't add a custom interface to avoid modprobing. All it adds is
unnecessary deviation. There's no benefit to echoing a selector to a custom
sysfs file compared to explicitly modprobing it.
Thanks.
--
tejun
next prev parent reply other threads:[~2022-02-24 2:07 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-17 3:13 [RFC V4 0/6] blk: make blk-rq-qos policies pluggable and modular Wang Jianchao (Kuaishou)
2022-02-17 3:13 ` [RFC V4 1/6] blk: prepare to make blk-rq-qos " Wang Jianchao (Kuaishou)
2022-02-17 8:48 ` Christoph Hellwig
2022-02-18 3:34 ` Wang Jianchao
2022-02-22 17:19 ` Tejun Heo
2022-02-23 3:08 ` Wang Jianchao
2022-02-23 3:10 ` Wang Jianchao
2022-02-23 21:37 ` Tejun Heo
2022-02-24 1:51 ` Wang Jianchao
2022-02-24 2:07 ` Tejun Heo [this message]
2022-02-24 2:50 ` Wang Jianchao
2022-02-24 16:53 ` Tejun Heo
2022-02-25 2:02 ` Wang Jianchao
2022-02-17 3:13 ` [RFC V4 2/6] blk-wbt: make wbt pluggable Wang Jianchao (Kuaishou)
2022-02-17 8:50 ` Christoph Hellwig
2022-02-18 3:41 ` Wang Jianchao
2022-02-22 8:12 ` Christoph Hellwig
2022-02-17 3:13 ` [RFC V4 3/6] blk-iolatency: make iolatency pluggable Wang Jianchao (Kuaishou)
2022-02-17 8:51 ` Christoph Hellwig
2022-02-18 3:42 ` Wang Jianchao
2022-02-17 3:13 ` [RFC V4 4/6] blk-iocost: make iocost pluggable Wang Jianchao (Kuaishou)
2022-02-17 8:52 ` Christoph Hellwig
2022-02-18 3:43 ` Wang Jianchao
2022-02-17 3:13 ` [RFC V4 5/6] blk-ioprio: make ioprio pluggable and modular Wang Jianchao (Kuaishou)
2022-02-17 8:54 ` Christoph Hellwig
2022-02-17 3:13 ` [RFC V4 6/6] blk: export the sysfs for switching qos Wang Jianchao (Kuaishou)
2022-02-17 8:55 ` Christoph Hellwig
2022-02-18 3:43 ` Wang Jianchao
2022-02-17 3:21 ` [RFC V4 0/6] blk: make blk-rq-qos policies pluggable and modular Jens Axboe
2022-02-17 3:53 ` Wang Jianchao
2022-02-17 8:43 ` Christoph Hellwig
2022-02-18 3:22 ` Wang Jianchao
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