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Subject: Re: [PATCH RFC v2 5/6] blk-throttle: support to destroy throtl_data
 when blk-throttle is disabled
To: Tejun Heo <tj@kernel.org>, Yu Kuai <yukuai1@huaweicloud.com>
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 "yukuai (C)" <yukuai3@huawei.com>
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From: Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <1bb85208-1224-77dc-f0b2-7b7a228ef70b@huaweicloud.com>
Date: Sat, 13 Apr 2024 10:06:00 +0800
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Hi,

?? 2024/04/13 2:05, Tejun Heo д??:
> Hello,
> 
> On Sat, Apr 06, 2024 at 04:00:58PM +0800, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> Currently once blk-throttle is enabled, it can't be destroyed until disk
>> removal, even it's disabled.
>>
>> Also prepare to support building it as kernel module.
> 
> The benefit of doing this whenever the ruleset becomes empty seems marginal.
> This isn't necessary to allow unloading blk-throttle and
> blkg_conf_exit_blkg() is also necessary because of this, right?

Yes, this is why blkg_conf_exit_blkg() is necessary.

I think that we need find an appropriate time to unload blk-throttle
other than deleting the gendisk. I also think of adding a new user input
like "8:0 free" to do this. These are the solutions that I can think of
for now.

Thanks,
Kuai

> 
> Thanks.
>