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Subject: Re: [PATCH] block: fix io hung by block throttle
From:   Junxiao Bi <junxiao.bi@oracle.com>
To:     Hillf Danton <hdanton@sina.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        axboe@kernel.dk
References: <20210414211830.5720-1-junxiao.bi@oracle.com>
 <20210417101008.4132-1-hdanton@sina.com>
 <20210418123342.13740-1-hdanton@sina.com>
 <1c3a2874-35bd-3ff0-3088-1a6ea968d016@oracle.com>
Message-ID: <9f02eb4d-4832-9f84-9df9-364f2000dd29@oracle.com>
Date:   Mon, 19 Apr 2021 09:39:30 -0700
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On 4/18/21 11:09 PM, Junxiao Bi wrote:
>> - finish_wait(&rqw->wait, &data.wq);
>> +    mutex_lock(&rqw->throttle_mutex);
>> +    wait_event(rqw->wait, acquire_inflight_cb(rqw, private_data));
>> +    mutex_unlock(&rqw->throttle_mutex);
>
> This will break the throttle? There is a inflight io limitation. With 
> this change, there can be only one io inflight whatever the limit is.
Sorry, ignore this. I should go sleep that time.
>
> Thanks,
>
> Junxiao.