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Date:   Tue, 31 Jan 2023 07:11:03 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Christoph Hellwig <hch@infradead.org>, linux-mmc@vger.kernel.org,
        Ulf Hansson <ulf.hansson@linaro.org>,
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        Paolo Valente <paolo.valente@linaro.org>
Subject: Re: [PATCH] mmc: core: Imply IOSCHED_BFQ
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On Tue, Jan 31, 2023 at 03:05:20PM +0100, Linus Walleij wrote:
> To be clear, "works better" in this context means, solving a problem
> for the interactive user, preventing random freezing of the UI on
> resource-limited (memory, disk throughput) systems under high
> I/O load.

Which already has nothing to do with the mmc driver.  And the rest
of your mail makes this even more clear.  You want bfq for interactive
systems with little resources and really shitty storage device, which
just happen to use mmc in your use case.

My use case for sd cards OTOH is extremely resource constrained systems
where I absolutely do not want a bloated I/O scheduler.  In fact I'd
love to be able to even compile the infrastructure for them away.

In other words:  you want distro policy to use bfq for your use case,
but that has no business being in the Kconfig.