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Subject: Re: [PATCH 08/10] blkcg: implement blk-iocost
From:   Paolo Valente <paolo.valente@linaro.org>
In-Reply-To: <20190911141630.GV2263813@devbig004.ftw2.facebook.com>
Date:   Wed, 11 Sep 2019 18:44:31 +0200
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To:     Tejun Heo <tj@kernel.org>
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> Il giorno 11 set 2019, alle ore 16:16, Tejun Heo <tj@kernel.org> ha =
scritto:
>=20
> Hello,
>=20
> On Wed, Sep 11, 2019 at 10:18:53AM +0200, Paolo Valente wrote:
>>> The two being enabled at the same time doesn't make sense, so we can
>>> just switch over to bfq when bfq is selected as the iosched.  I =
asked
>>> what Paolo wanted to do in terms of interface a couple times now but
>>> didn't get an answer and he posted a patch which makes the two
>>> controllers conflict, so....  Paolo, so it looks like you want to
>>> rename all bfq files to drop the bfq prefix, right?
>>=20
>> Yep, mainly because ... this is the solution you voted and you
>> yourself proposed [1] :)
>>=20
>> [1] https://patchwork.kernel.org/patch/10988261/
>=20
> So, that was then.  Since then the interface change has been published
> and userspace, at least some of them, already had to adjust.  Now, I
> don't have any opinion on the matter and flipping again will cause
> inconveniences to some subset of users.  It's your call.
>=20

Ok, then let's go for removing bfq prefix, as expected, e.g., by
systemd community [1].  A few days ago I reposted a patch removing the
prefix from all involved parameters [2], it should make all legacy
software work again.

[1] https://github.com/systemd/systemd/issues/7057
[2] https://lkml.org/lkml/2019/9/9/47

>>> I can implement
>>> the switching if so.
>>=20
>> That would be perfect.
>=20
> Whichever way it gets decided, this is easy enough.  I'll prep a
> patch.
>=20

Thank you for that too,
Paolo

> Thanks.
>=20
> --=20
> tejun