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Subject: Re: [PATCH 2/2] block, bfq: delete "bfq" prefix from cgroup filenames
From:   Paolo Valente <paolo.valente@linaro.org>
In-Reply-To: <20190918151948.GL3084169@devbig004.ftw2.facebook.com>
Date:   Wed, 18 Sep 2019 18:19:42 +0200
Cc:     Jens Axboe <axboe@kernel.dk>,
        linux-block <linux-block@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
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        cgroups@vger.kernel.org, Angelo Ruocco <angeloruocco90@gmail.com>
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References: <20190917165148.19146-1-paolo.valente@linaro.org>
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To:     Tejun Heo <tj@kernel.org>
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> Il giorno 18 set 2019, alle ore 17:19, Tejun Heo <tj@kernel.org> ha =
scritto:
>=20
> Hello,
>=20
> On Wed, Sep 18, 2019 at 07:18:50AM +0200, Paolo Valente wrote:
>> A solution that both fulfills userspace request and doesn't break
>> anything for hypothetical users of the current interface already made
>> it to mainline, and Linus liked it too.  It is:
>=20
> Linus didn't like it.  The implementation was a bit nasty.  That was
> why it became a subject in the first place.
>=20
>> 19e9da9e86c4 ("block, bfq: add weight symlink to the bfq.weight =
cgroup parameter")
>>=20
>> But it was then reverted on Tejun's request to do exactly what we
>> don't want do any longer now:
>> cf8929885de3 ("cgroup/bfq: revert bfq.weight symlink change")
>=20
> Note that the interface was wrong at the time too.
>=20
>> So, Jens, Tejun, can we please just revert that revert?
>=20
> I think presenting both io.weight and io.bfq.weight interfaces are
> probably the best course of action at this point but why does it have
> to be a symlink?  What's wrong with just creating another file with
> the same backing function?
>=20

I think a symlink would be much clearer for users, given the confusion
already caused by two names for the same parameter.  But let's hear
others' opinion too.

Thanks,
Paolo

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