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Date:   Thu, 24 Feb 2022 05:46:30 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     "Wang Jianchao (Kuaishou)" <jianchao.wan9@gmail.com>
Cc:     Jens Axboe <axboe@kernel.dk>, Josef Bacik <jbacik@fb.com>,
        Tejun Heo <tj@kernel.org>,
        Bart Van Assche <bvanassche@acm.org>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC V5 10/16] blk-wbt: get rid of wbt_enable/disable_default()
Message-ID: <YheMNqrhxp6r/AhH@infradead.org>
References: <20220224090654.54671-1-jianchao.wan9@gmail.com>
 <20220224090654.54671-11-jianchao.wan9@gmail.com>
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On Thu, Feb 24, 2022 at 05:06:48PM +0800, Wang Jianchao (Kuaishou) wrote:
> wbt_enable_default() is used to open wbt feature by default.
> wbt_disable_default() is only employed by bfq which has similar
> writeback throttling mechanism. This kind of policy should be
> selected by the user instead of being set in kernel. This patch
> get rid of the interfaces and let the user configure appropricate
> blk-rq-qos policy by themselves.

This drastically changes the user visible behavior.