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Subject: Re: [PATCH] blk-throttle: don't check whether or not lower limit is
 valid if CONFIG_BLK_DEV_THROTTLING_LOW is off
To:     Yu Kuai <yukuai3@huawei.com>, tj@kernel.org
Cc:     cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yi.zhang@huawei.com,
        zhangxiaoxu5@huawei.com
References: <20201126031834.40807-1-yukuai3@huawei.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <51844d83-3447-cf0f-bde2-d368f5f43f5a@kernel.dk>
Date:   Wed, 2 Dec 2020 12:44:38 -0700
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On 11/25/20 8:18 PM, Yu Kuai wrote:
> blk_throtl_update_limit_valid() will search for descendants to see if
> 'LIMIT_LOW' of bps/iops and READ/WRITE is nonzero. However, they're always
> zero if CONFIG_BLK_DEV_THROTTLING_LOW is not set, furthermore, a lot of
> time will be wasted to iterate descendants.
> 
> Thus do nothing in blk_throtl_update_limit_valid() in such situation.

Applied, thanks.

-- 
Jens Axboe