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Message-ID: <d7ed009d-09af-935b-f905-fef7d02f1649@kernel.dk>
Date:   Sun, 27 Feb 2022 14:51:46 -0700
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Subject: Re: [PATCH v9] block: cancel all throttled bios in del_gendisk()
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To:     Christoph Hellwig <hch@infradead.org>, Yu Kuai <yukuai3@huawei.com>
Cc:     ming.lei@redhat.com, tj@kernel.org, cgroups@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com
References: <20220210115637.1074927-1-yukuai3@huawei.com>
 <YhuyBgZSS6m/Mwu6@infradead.org>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <YhuyBgZSS6m/Mwu6@infradead.org>
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On 2/27/22 10:16 AM, Christoph Hellwig wrote:
> On Thu, Feb 10, 2022 at 07:56:37PM +0800, Yu Kuai wrote:
>> Throttled bios can't be issued after del_gendisk() is done, thus
>> it's better to cancel them immediately rather than waiting for
>> throttle is done.
>>
>> For example, if user thread is throttled with low bps while it's
>> issuing large io, and the device is deleted. The user thread will
>> wait for a long time for io to return.
> 
> FYI, this crashed left rigt and center when running xfstests with
> traces pointing to throtl_pending_timer_fn.

Dropped for now.

-- 
Jens Axboe