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Sender: Tejun Heo <htejun@gmail.com>
Date:   Wed, 23 Nov 2022 08:31:55 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Kemeng Shi <shikemeng@huawei.com>
Cc:     josef@toxicpanda.com, axboe@kernel.dk, cgroups@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 09/11] blk-throttle: remove unnecessary check for
 validation of limit index
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References: <20221123060401.20392-1-shikemeng@huawei.com>
 <20221123060401.20392-10-shikemeng@huawei.com>
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On Wed, Nov 23, 2022 at 02:03:59PM +0800, Kemeng Shi wrote:
> We always keep limit index valid as following:
> Max limit is always valid and low limit can only be invalidated in
> blk_throtl_update_limit_valid. Each time low limit may become invalid
> after blk_throtl_update_limit_valid is called, we will check and make
> sure current limit index is valid.
> 
> It's reasonable to always keep limit index valid, so we can remove this
> check.

It's not obvious to me that it's correct and I'm not sure what we're gaining
by removing this while risking subtle breakages.

-- 
tejun