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Subject: Re: [PATCH] blk-mq: run queue after issuing the last request of the
 plug list
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To:     Ming Lei <ming.lei@redhat.com>
CC:     Yu Kuai <yukuai3@huawei.com>, Yu Kuai <yukuai1@huaweicloud.com>,
        <axboe@kernel.dk>, <linux-block@vger.kernel.org>, <hch@lst.de>,
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From:   Yufen Yu <yuyufen@huawei.com>
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On 2022/7/26 15:39, Ming Lei wrote:
> On Tue, Jul 26, 2022 at 01:01:41PM +0800, Yufen Yu wrote:
>>
>>>
>>
>> hi Ming,
>>
>> Here rq2 fail from blk_mq_plug_issue_direct() in blk_mq_flush_plug_list(),
>> not blk_mq_sched_insert_requests
> 
> OK, just wondering why Yufen's patch touches
> blk_mq_sched_insert_requests().
> 
> Here the issue is in blk_mq_plug_issue_direct() itself, it is wrong to use last
> request of plug list to decide if run queue is needed since all the remained
> requests in plug list may be from other hctxs, and the simplest fix could be pass
> run_queue as true always to blk_mq_request_bypass_insert().
> 


OK, thanks for your suggestion and I will send v2.

Thanks,
Yufen

> 
> Thanks,
> Ming
> 
> .