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Date:   Fri, 25 Mar 2022 01:46:44 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Yu Kuai <yukuai3@huawei.com>
Cc:     axboe@kernel.dk, mpatocka@redhat.com, snitzer@redhat.com,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com
Subject: Re: [PATCH 1/3] block: don't show disk stats if io accounting is
 disabled
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On Thu, Mar 17, 2022 at 07:26:51PM +0800, Yu Kuai wrote:
> If io accounting is disabled, there is no point to handle such device
> in diskstats_show(), and it can be confused for users because all fields
> in iostat are zero while the disk is handling io.

But changing the output will break existing users looking at it.