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From:   Khazhy Kumykov <khazhy@chromium.org>
Date:   Mon, 17 Oct 2022 10:22:59 -0700
Message-ID: <CACGdZYKcpHG_bWew_K78CgwDYMQAGfXX+QU4-9PNoV1j2E1a0g@mail.gmail.com>
Subject: Re: [PATCH] block: allow specifying default iosched in config
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Damien Le Moal <damien.lemoal@opensource.wdc.com>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Mon, Oct 10, 2022 at 12:20 AM Christoph Hellwig <hch@infradead.org> wrote:
>
> On Tue, Oct 04, 2022 at 04:15:20PM -0700, Khazhy Kumykov wrote:
> > The kernel already picks and hardcodes a default scheduler, my
> > thinking is: why not let folks choose? This was allowed in the old
> > block layer since 2005.
>
> You can choose it using CONFIG_CMDLINE.  We can't add a config option
> for every bloody default as that simply does not scale.

Are you referring to elevator=? It looks like that needs to be
re-wired for blk-mq, but seems like a reasonable solution. I'll send a
new patch out.

Thanks,
Khazhy