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Subject: Re: [PATCH 09/11] blk-throttle: remove unnecessary check for
 validation of limit index
To:     Tejun Heo <tj@kernel.org>
CC:     <josef@toxicpanda.com>, <axboe@kernel.dk>,
        <cgroups@vger.kernel.org>, <linux-block@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20221123060401.20392-1-shikemeng@huawei.com>
 <20221123060401.20392-10-shikemeng@huawei.com>
 <Y35nG1CguzXf0GX8@slm.duckdns.org>
From:   Kemeng Shi <shikemeng@huawei.com>
Message-ID: <95ff6d32-7f4e-8ae3-8c95-4ce8ff111330@huawei.com>
Date:   Thu, 24 Nov 2022 20:58:50 +0800
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on 11/24/2022 2:31 AM, Tejun Heo wrote:
> 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.
I will remove this patch in next version.

-- 
Best wishes
Kemeng Shi