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Subject: Re: [PATCH] blk-wbt: get back the missed wakeup from __wbt_done
To:     Jens Axboe <axboe@kernel.dk>, Anchal Agarwal <anchalag@amzn.com>
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From:   "jianchao.wang" <jianchao.w.wang@oracle.com>
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Date:   Tue, 28 Aug 2018 10:52:57 +0800
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Hi Jens

On 08/27/2018 10:51 PM, Jens Axboe wrote:
>>> I cannot get the point of "since we can't rely on just being woken from the ->func handler
>>> we set".
>>> Do you mean there could be someone else could wake up this task ?
> Yeah, you don't know for a fact that the wbt wait queue is the only
> guy waking us up. Any sleep like this needs a loop. It was quite
> easy to reproduce for me, and as expected, you'll get list corruption
> on the wait queue since we leave it on the list and the stack goes
> away.
> 
Yes, got it. Thanks for your kindly response. :)

Thanks
Jianchao